Vulnerability-Lookup

BDU:2026-10384 (CVE-2026-27858)

Vulnerability from fstec – Published: 2026-07-23 – Updated: 2026-08-31 – View on bdu.fstec.ru Fixed

Title

Уязвимость службы ManageSieve почтовых серверов Dovecot и OX Dovecot Pro, связанная с неконтролируемым расходом ресурсов, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость службы ManageSieve почтовых серверов Dovecot и OX Dovecot Pro связана с неконтролируемым расходом ресурсов. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, вызвать отказ в обслуживании

Severity

7.8 (High) CVSS 2.0


                      
                        AV:N/AC:L/Au:N/C:N/I:N/A:C

7.5 (High) CVSS 3.1


                      
                        CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Resource exhaustion

Incidents

Being clarified

Remediation

Software update

CWE

CWE-400 - Неконтролируемый расход ресурса («Истощение ресурса»)
CWE-770 - Неограниченное распределение ресурсов или дросселирование

Aliases

CVE-2026-27858

References

10 references

URL
https://github.com/advisories/GHSA-xr7v-hj32-mr4r
https://bugzilla.redhat.com/show_bug.cgi?id=2452175
https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/ox…
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27858.json
https://redos.red-soft.ru/search/?iblock_id=24&q=CVE-2026-27858
https://explore.alas.aws.amazon.com/CVE-2026-27858.html
https://access.redhat.com/security/cve/cve-2026-27858
https://cve.basealt.ru/tag/cve-2025-59031.html
https://altsp.su/obnovleniya-bezopasnosti/
https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17

Impacted products

7 products from 8 vendors

Vendors

Red Hat, Inc., ООО «Ред Софт», ООО «РусБИТех-Астра», Amazon.com Inc., АО «ИВК», Timo Sirainen, Open-Xchange

Products

Red Hat Enterprise Linux, РЕД ОС (запись в едином реестре российских программ №3751), Astra Linux Special Edition (запись в едином реестре российских программ №369), Amazon Linux, АЛЬТ СП 10, Dovecot, OX Dovecot Pro

Versions

6 (Red Hat Enterprise Linux), 8 (Red Hat Enterprise Linux), 7.3 (РЕД ОС), 1.7 (Astra Linux Special Edition), 9 (Red Hat Enterprise Linux), 2023 (Amazon Linux), 8.4 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), - (АЛЬТ СП 10), 9.0 Update Services for SAP Solutions (Red Hat Enterprise Linux), 8.6 Update Services for SAP Solutions (Red Hat Enterprise Linux), 8.6 Telecommunications Update Service (Red Hat Enterprise Linux), 8.6 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), 7 Extended Lifecycle Support (Red Hat Enterprise Linux), 9.4 Extended Update Support (Red Hat Enterprise Linux), 10 (Red Hat Enterprise Linux), 8.8 Telecommunications Update Service (Red Hat Enterprise Linux), 8.8 Update Services for SAP Solutions (Red Hat Enterprise Linux), 9.2 Update Services for SAP Solutions (Red Hat Enterprise Linux), 8.4 Extended Update Support Long-Life Add-On (Red Hat Enterprise Linux), 9.6 Extended Update Support (Red Hat Enterprise Linux), 8.0 (РЕД ОС), 10.0 Extended Update Support (Red Hat Enterprise Linux), до 2.4.3 (Dovecot), до 2.3.22.1 (OX Dovecot Pro), от 3.0.0 до 3.0.5 (OX Dovecot Pro), от 3.1.0 до 3.1.4 (OX Dovecot Pro)

Product types

Operating system, Network software, Application software

Platforms

Red Hat, Inc. Red Hat Enterprise Linux 6, Inc. Red Hat Enterprise Linux 8, ООО «Ред Софт» РЕД ОС 7.3 (запись в едином реестре российских программ №3751), ООО «РусБИТех-Астра» Astra Linux Special Edition 1.7 (запись в едином реестре российских программ №369), Inc. Red Hat Enterprise Linux 9, Amazon.com Inc. Amazon Linux 2023, Inc. Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support, АО «ИВК» АЛЬТ СП 10 -, Inc. Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions, Inc. Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions, Inc. Red Hat Enterprise Linux 8.6 Telecommunications Update Service, Inc. Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support, Inc. Red Hat Enterprise Linux 7 Extended Lifecycle Support, Inc. Red Hat Enterprise Linux 9.4 Extended Update Support, Inc. Red Hat Enterprise Linux 10, Inc. Red Hat Enterprise Linux 8.8 Telecommunications Update Service, Inc. Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions, Inc. Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions, Inc. Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On, Inc. Red Hat Enterprise Linux 9.6 Extended Update Support, ООО «Ред Софт» РЕД ОС 8.0 (запись в едином реестре российских программ №3751), Inc. Red Hat Enterprise Linux 10.0 Extended Update Support

Mitigations

Использование рекомендаций: Для Dovecot: https://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json Для Ред ОС: https://redos.red-soft.ru/search/?iblock_id=24&q=CVE-2026-27858 Для программных продуктов Red Hat Inc.: https://access.redhat.com/security/cve/cve-2026-27858 Для Amazon Linux: https://explore.alas.aws.amazon.com/CVE-2026-27858.html Для АЛЬТ СП 10: https://cve.basealt.ru/tag/cve-2025-59031.html Для ОС АЛЬТ СП 10: установка обновления из публичного репозитория программного средства: https://altsp.su/obnovleniya-bezopasnosti/ Для ОС Astra Linux: обновить пакет dovecot до 1:2.3.19.1+dfsg1-2.1+deb12u6.astra17+p4 или более высокой версии, используя рекомендации производителя: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:N/C:N/I:N/A:C",
  "CVSS 3.0": "AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Red Hat, Inc., \u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb, \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb, Amazon.com Inc., \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb, Timo Sirainen, Open-Xchange",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "6 (Red Hat Enterprise Linux), 8 (Red Hat Enterprise Linux), 7.3 (\u0420\u0415\u0414 \u041e\u0421), 1.7 (Astra Linux Special Edition), 9 (Red Hat Enterprise Linux), 2023 (Amazon Linux), 8.4 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), - (\u0410\u041b\u042c\u0422 \u0421\u041f 10), 9.0 Update Services for SAP Solutions (Red Hat Enterprise Linux), 8.6 Update Services for SAP Solutions (Red Hat Enterprise Linux), 8.6 Telecommunications Update Service (Red Hat Enterprise Linux), 8.6 Advanced Mission Critical Update Support (Red Hat Enterprise Linux), 7 Extended Lifecycle Support (Red Hat Enterprise Linux), 9.4 Extended Update Support (Red Hat Enterprise Linux), 10 (Red Hat Enterprise Linux), 8.8 Telecommunications Update Service (Red Hat Enterprise Linux), 8.8 Update Services for SAP Solutions (Red Hat Enterprise Linux), 9.2 Update Services for SAP Solutions (Red Hat Enterprise Linux), 8.4 Extended Update Support Long-Life Add-On (Red Hat Enterprise Linux), 9.6 Extended Update Support (Red Hat Enterprise Linux), 8.0 (\u0420\u0415\u0414 \u041e\u0421), 10.0 Extended Update Support (Red Hat Enterprise Linux), \u0434\u043e 2.4.3 (Dovecot), \u0434\u043e 2.3.22.1 (OX Dovecot Pro), \u043e\u0442 3.0.0 \u0434\u043e 3.0.5 (OX Dovecot Pro), \u043e\u0442 3.1.0 \u0434\u043e 3.1.4 (OX Dovecot Pro)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\n\u0414\u043b\u044f Dovecot:\nhttps://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json\n\n\u0414\u043b\u044f \u0420\u0435\u0434 \u041e\u0421:\nhttps://redos.red-soft.ru/search/?iblock_id=24\u0026q=CVE-2026-27858\n\n\u0414\u043b\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u044b\u0445 \u043f\u0440\u043e\u0434\u0443\u043a\u0442\u043e\u0432 Red Hat Inc.:\nhttps://access.redhat.com/security/cve/cve-2026-27858\n\n\u0414\u043b\u044f Amazon Linux:\nhttps://explore.alas.aws.amazon.com/CVE-2026-27858.html\n\n\u0414\u043b\u044f \u0410\u041b\u042c\u0422 \u0421\u041f 10:\nhttps://cve.basealt.ru/tag/cve-2025-59031.html\n\n\u0414\u043b\u044f \u041e\u0421 \u0410\u041b\u042c\u0422 \u0421\u041f 10: \u0443\u0441\u0442\u0430\u043d\u043e\u0432\u043a\u0430 \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f \u0438\u0437 \u043f\u0443\u0431\u043b\u0438\u0447\u043d\u043e\u0433\u043e \u0440\u0435\u043f\u043e\u0437\u0438\u0442\u043e\u0440\u0438\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430: https://altsp.su/obnovleniya-bezopasnosti/\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n\u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 dovecot \u0434\u043e 1:2.3.19.1+dfsg1-2.1+deb12u6.astra17+p4 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0438 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "27.03.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "31.08.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "23.07.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-10384",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2026-27858",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Red Hat Enterprise Linux, \u0420\u0415\u0414 \u041e\u0421 (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21163751), Astra Linux Special Edition (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), Amazon Linux, \u0410\u041b\u042c\u0422 \u0421\u041f 10, Dovecot, OX Dovecot Pro",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": "Red Hat, Inc. Red Hat Enterprise Linux 6 , Red Hat, Inc. Red Hat Enterprise Linux 8 , \u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb \u0420\u0415\u0414 \u041e\u0421 7.3  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21163751), \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb Astra Linux Special Edition 1.7  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u2116369), Red Hat, Inc. Red Hat Enterprise Linux 9 , Amazon.com Inc. Amazon Linux 2023 , Red Hat, Inc. Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support , \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb \u0410\u041b\u042c\u0422 \u0421\u041f 10 - , Red Hat, Inc. Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions , Red Hat, Inc. Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions , Red Hat, Inc. Red Hat Enterprise Linux 8.6 Telecommunications Update Service , Red Hat, Inc. Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support , Red Hat, Inc. Red Hat Enterprise Linux 7 Extended Lifecycle Support , Red Hat, Inc. Red Hat Enterprise Linux 9.4 Extended Update Support , Red Hat, Inc. Red Hat Enterprise Linux 10 , Red Hat, Inc. Red Hat Enterprise Linux 8.8 Telecommunications Update Service , Red Hat, Inc. Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions , Red Hat, Inc. Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions , Red Hat, Inc. Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On , Red Hat, Inc. Red Hat Enterprise Linux 9.6 Extended Update Support , \u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb \u0420\u0415\u0414 \u041e\u0421 8.0  (\u0437\u0430\u043f\u0438\u0441\u044c \u0432 \u0435\u0434\u0438\u043d\u043e\u043c \u0440\u0435\u0435\u0441\u0442\u0440\u0435 \u0440\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u0438\u0445 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c \u21163751), Red Hat, Inc. Red Hat Enterprise Linux 10.0 Extended Update Support ",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0441\u043b\u0443\u0436\u0431\u044b ManageSieve \u043f\u043e\u0447\u0442\u043e\u0432\u044b\u0445 \u0441\u0435\u0440\u0432\u0435\u0440\u043e\u0432 Dovecot \u0438 OX Dovecot Pro, \u0441\u0432\u044f\u0437\u0430\u043d\u043d\u0430\u044f \u0441 \u043d\u0435\u043a\u043e\u043d\u0442\u0440\u043e\u043b\u0438\u0440\u0443\u0435\u043c\u044b\u043c \u0440\u0430\u0441\u0445\u043e\u0434\u043e\u043c \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u043a\u043e\u043d\u0442\u0440\u043e\u043b\u0438\u0440\u0443\u0435\u043c\u044b\u0439 \u0440\u0430\u0441\u0445\u043e\u0434 \u0440\u0435\u0441\u0443\u0440\u0441\u0430 (\u00ab\u0418\u0441\u0442\u043e\u0449\u0435\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u0430\u00bb) (CWE-400), \u041d\u0435\u043e\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u043d\u043e\u0435 \u0440\u0430\u0441\u043f\u0440\u0435\u0434\u0435\u043b\u0435\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432 \u0438\u043b\u0438 \u0434\u0440\u043e\u0441\u0441\u0435\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 (CWE-770)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0441\u043b\u0443\u0436\u0431\u044b ManageSieve \u043f\u043e\u0447\u0442\u043e\u0432\u044b\u0445 \u0441\u0435\u0440\u0432\u0435\u0440\u043e\u0432 Dovecot \u0438 OX Dovecot Pro \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u043a\u043e\u043d\u0442\u0440\u043e\u043b\u0438\u0440\u0443\u0435\u043c\u044b\u043c \u0440\u0430\u0441\u0445\u043e\u0434\u043e\u043c \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e, \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u0418\u0441\u0447\u0435\u0440\u043f\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://github.com/advisories/GHSA-xr7v-hj32-mr4r\nhttps://bugzilla.redhat.com/show_bug.cgi?id=2452175\nhttps://documentation.open-xchange.com/dovecot/security/advisories/csaf/2026/oxdc-adv-2026-0001.json\nhttps://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-27858.json\nhttps://redos.red-soft.ru/search/?iblock_id=24\u0026q=CVE-2026-27858\nhttps://explore.alas.aws.amazon.com/CVE-2026-27858.html\nhttps://access.redhat.com/security/cve/cve-2026-27858\nhttps://cve.basealt.ru/tag/cve-2025-59031.html\nhttps://altsp.su/obnovleniya-bezopasnosti/\nhttps://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u0430\u044f \u0441\u0438\u0441\u0442\u0435\u043c\u0430, \u0421\u0435\u0442\u0435\u0432\u043e\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0435 \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u043e, \u041f\u0440\u0438\u043a\u043b\u0430\u0434\u043d\u043e\u0435 \u041f\u041e \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u043e\u043d\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-400, CWE-770",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,8)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,5)"
}

CVE-2026-27858 (GCVE-0-2026-27858)

Vulnerability from cvelistv5 – Published: 2026-03-27 08:10 – Updated: 2026-07-15 01:12

Summary

Attacker can send a specifically crafted message before authentication that causes managesieve to allocate large amount of memory. Attacker can force managesieve-login to be unavailable by repeatedly crashing the process. Protect access to managesieve protocol, or install fixed version. No publicly available exploits are known.

Severity

7.5 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-03-27 12:36 UTC

CWE

CWE-400 - Uncontrolled Resource Consumption
CWE-770 - Allocation of Resources Without Limits or Throttling

Assigner

OX mitre root

References

18 references

URL	Tags
https://documentation.open-xchange.com/dovecot/se…	vendor-advisory
https://access.redhat.com/security/cve/CVE-2026-27858	vdb-entryx_refsource_REDHAT
https://bugzilla.redhat.com/show_bug.cgi?id=2452175	issue-trackingx_refsource_REDHAT
https://security.access.redhat.com/data/csaf/v2/v…	x_sadp-csaf-vex
https://access.redhat.com/errata/RHSA-2026:26564	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17602	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:13498	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19149	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:13830	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19455	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19453	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:18053	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17630	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17628	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17625	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:17626	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:13857	vendor-advisoryx_refsource_REDHAT
https://access.redhat.com/errata/RHSA-2026:19364	vendor-advisoryx_refsource_REDHAT

Impacted products

18 products

Vendor	Product	Version
Open-Xchange GmbH	OX Dovecot Pro	Affected: 0 , ≤ 2.3.0 (semver) Affected: 0 , ≤ 3.1.0 (semver) Affected: 0 , ≤ 2.4.0 (semver)
Red Hat	Red Hat Enterprise Linux 10	Unaffected: 1:2.3.21-16.el10_1.1 , < * (rpm) Unaffected: 1:2.3.21-19.el10_2 , < * (rpm) cpe:/o:redhat:enterprise_linux:10.1 cpe:/o:redhat:enterprise_linux:10.2
Red Hat	Red Hat Enterprise Linux 10.0 Extended Update Support	Unaffected: 1:2.3.21-16.el10_0.1 , < * (rpm) cpe:/o:redhat:enterprise_linux_eus:10.0
Red Hat	Red Hat Enterprise Linux 7 Extended Lifecycle Support	Unaffected: 1:2.2.36-8.el7_9.1 , < * (rpm) cpe:/o:redhat:rhel_els:7
Red Hat	Red Hat Enterprise Linux 8	Unaffected: 1:2.3.16-7.el8_10 , < * (rpm) cpe:/a:redhat:enterprise_linux:8
Red Hat	Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support	Unaffected: 1:2.3.8-9.el8_4.1 , < * (rpm) cpe:/a:redhat:rhel_aus:8.4
Red Hat	Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On	Unaffected: 1:2.3.8-9.el8_4.1 , < * (rpm) cpe:/a:redhat:rhel_eus_long_life:8.4
Red Hat	Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support	Unaffected: 1:2.3.16-2.el8_6.1 , < * (rpm) cpe:/a:redhat:rhel_aus:8.6
Red Hat	Red Hat Enterprise Linux 8.6 Telecommunications Update Service	Unaffected: 1:2.3.16-2.el8_6.1 , < * (rpm) cpe:/a:redhat:rhel_tus:8.6
Red Hat	Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions	Unaffected: 1:2.3.16-2.el8_6.1 , < * (rpm) cpe:/a:redhat:rhel_e4s:8.6
Red Hat	Red Hat Enterprise Linux 8.8 Telecommunications Update Service	Unaffected: 1:2.3.16-3.el8_8.1 , < * (rpm) cpe:/a:redhat:rhel_tus:8.8
Red Hat	Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions	Unaffected: 1:2.3.16-3.el8_8.1 , < * (rpm) cpe:/a:redhat:rhel_e4s:8.8
Red Hat	Red Hat Enterprise Linux 9	Unaffected: 1:2.3.16-15.el9_7.1 , < * (rpm) Unaffected: 1:2.3.16-18.el9_8 , < * (rpm) cpe:/a:redhat:enterprise_linux:9
Red Hat	Red Hat Enterprise Linux 9.0 Update Services for SAP Solutions	Unaffected: 1:2.3.16-3.el9_0.1 , < * (rpm) cpe:/a:redhat:rhel_e4s:9.0
Red Hat	Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions	Unaffected: 1:2.3.16-8.el9_2.2 , < * (rpm) cpe:/a:redhat:rhel_e4s:9.2
Red Hat	Red Hat Enterprise Linux 9.4 Extended Update Support	Unaffected: 1:2.3.16-11.el9_4.2 , < * (rpm) cpe:/a:redhat:rhel_eus:9.4
Red Hat	Red Hat Enterprise Linux 9.6 Extended Update Support	Unaffected: 1:2.3.16-15.el9_6.1 , < * (rpm) cpe:/a:redhat:rhel_eus:9.6
Red Hat	Red Hat Enterprise Linux 6	cpe:/o:redhat:enterprise_linux:6

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{
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                "id": "CVE-2026-27858",
                "options": [
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                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
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                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-03-27T12:36:26.526829Z",
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            "packageName": "dovecot",
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          },
          {
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          },
          {
            "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
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              "cpe:/a:redhat:rhel_eus_long_life:8.4"
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          },
          {
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            "defaultStatus": "affected",
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            "defaultStatus": "affected",
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          },
          {
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            "defaultStatus": "affected",
            "packageName": "dovecot",
            "product": "Red Hat Enterprise Linux 8.6 Update Services for SAP Solutions",
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            "versions": [
              {
                "lessThan": "*",
                "status": "unaffected",
                "version": "1:2.3.16-2.el8_6.1",
                "versionType": "rpm"
              }
            ]
          },
          {
            "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
            "cpes": [
              "cpe:/a:redhat:rhel_tus:8.8"
            ],
            "defaultStatus": "affected",
            "packageName": "dovecot",
            "product": "Red Hat Enterprise Linux 8.8 Telecommunications Update Service",
            "vendor": "Red Hat",
            "versions": [
              {
                "lessThan": "*",
                "status": "unaffected",
                "version": "1:2.3.16-3.el8_8.1",
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          },
          {
            "collectionURL": "https://access.redhat.com/downloads/content/package-browser/",
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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Detection rules are retrieved from Rulezet.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.