Vulnerability-Lookup

BDU:2026-12847 (CVE-2026-40355)

Vulnerability from fstec – Published: 2026-08-28 – Updated: 2026-08-28 – View on bdu.fstec.ru Fixed

Title

Уязвимость сетевого протокола аутентификации Kerberos, связанная с ошибками разыменования указателя, позволяющая нарушителю вызвать отказ в обслуживании

Summary

Уязвимость сетевого протокола аутентификации Kerberos связана с ошибками разыменования указателя. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, вызвать отказ в обслуживании

Severity

5.4 (Medium) CVSS 2.0


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

5.9 (Medium) CVSS 3.1


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

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-476 - Разыменование указателя NULL

Aliases

CVE-2026-40355

References

8 references

URL
https://nvd.nist.gov/vuln/detail/CVE-2026-40355
https://security-tracker.debian.org/tracker/CVE-2026-40355
https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f
https://web.mit.edu/kerberos/advisories/
https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17
https://deb.freexian.com/extended-lts/tracker/CVE-2026-40355
https://ubuntu.com/security/CVE-2026-40355
https://access.redhat.com/security/cve/CVE-2026-40355

Impacted products

9 products from 6 vendors

Vendors

Red Hat, Inc., Сообщество свободного программного обеспечения, ООО «РусБИТех-Астра», Canonical Ltd., MIT

Products

Red Hat Enterprise Linux, Debian GNU/Linux, Astra Linux Special Edition (запись в едином реестре российских программ №369), Red Hat OpenShift Container Platform, Ubuntu, Red Hat Discovery, Red Hat Update Infrastructure, Red Hat Insights proxy, Kerberos

Versions

6 (Red Hat Enterprise Linux), 7 (Red Hat Enterprise Linux), 8 (Red Hat Enterprise Linux), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 1.7 (Astra Linux Special Edition), 4 (Red Hat OpenShift Container Platform), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), 24.04 LTS (Ubuntu), 10 (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), 2 (Red Hat Discovery), 5 (Red Hat Update Infrastructure), 1.5 (Red Hat Insights proxy), 26.04 LTS (Ubuntu), до 1.22.3 (Kerberos)

Product types

Operating system, Application software

Platforms

Red Hat, Inc. Red Hat Enterprise Linux 6, Inc. Red Hat Enterprise Linux 7, Inc. Red Hat Enterprise Linux 8, Сообщество свободного программного обеспечения Debian GNU/Linux 11, Сообщество свободного программного обеспечения Debian GNU/Linux 12, ООО «РусБИТех-Астра» Astra Linux Special Edition 1.7 (запись в едином реестре российских программ №369), Canonical Ltd. Ubuntu 22.04 LTS, Inc. Red Hat Enterprise Linux 9, Canonical Ltd. Ubuntu 24.04 LTS, Inc. Red Hat Enterprise Linux 10, Сообщество свободного программного обеспечения Debian GNU/Linux 13, Canonical Ltd. Ubuntu 26.04 LTS

Mitigations

В условиях отсутствия обновлений безопасности от производителя рекомендуется придерживаться "Рекомендаций по безопасной настройке операционных систем LINUX", изложенных в методическом документе ФСТЭК России, утверждённом 25 декабря 2022 года. Использование рекомендаций: Для Kerberos: https://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f Для Debian GNU/Linux: https://security-tracker.debian.org/tracker/CVE-2026-40355 https://deb.freexian.com/extended-lts/tracker/CVE-2026-40355 Для ОС Astra Linux: обновить пакет krb5 до 1.19.2-2ubuntu0.7astra7 или более высокой версии: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17 Для Ubuntu: https://ubuntu.com/security/CVE-2026-40355 Для программных продуктов Red Hat, Inc.: https://access.redhat.com/security/cve/CVE-2026-40355

Credits

Исследователь: Cem Onat Karagun

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:H/Au:N/C:N/I:N/A:C",
  "CVSS 3.0": "AV:N/AC:H/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., \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f, \u041e\u041e\u041e \u00ab\u0420\u0443\u0441\u0411\u0418\u0422\u0435\u0445-\u0410\u0441\u0442\u0440\u0430\u00bb, Canonical Ltd., MIT",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "6 (Red Hat Enterprise Linux), 7 (Red Hat Enterprise Linux), 8 (Red Hat Enterprise Linux), 11 (Debian GNU/Linux), 12 (Debian GNU/Linux), 1.7 (Astra Linux Special Edition), 4 (Red Hat OpenShift Container Platform), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), 24.04 LTS (Ubuntu), 10 (Red Hat Enterprise Linux), 13 (Debian GNU/Linux), 2 (Red Hat Discovery), 5 (Red Hat Update Infrastructure), 1.5 (Red Hat Insights proxy), 26.04 LTS (Ubuntu), \u0434\u043e 1.22.3 (Kerberos)",
  "\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": "\u0412 \u0443\u0441\u043b\u043e\u0432\u0438\u044f\u0445 \u043e\u0442\u0441\u0443\u0442\u0441\u0442\u0432\u0438\u044f \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0439 \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u043e\u0442 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u044f \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0443\u0435\u0442\u0441\u044f \u043f\u0440\u0438\u0434\u0435\u0440\u0436\u0438\u0432\u0430\u0442\u044c\u0441\u044f \"\u0420\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439 \u043f\u043e \u0431\u0435\u0437\u043e\u043f\u0430\u0441\u043d\u043e\u0439 \u043d\u0430\u0441\u0442\u0440\u043e\u0439\u043a\u0435 \u043e\u043f\u0435\u0440\u0430\u0446\u0438\u043e\u043d\u043d\u044b\u0445 \u0441\u0438\u0441\u0442\u0435\u043c LINUX\", \u0438\u0437\u043b\u043e\u0436\u0435\u043d\u043d\u044b\u0445 \u0432 \u043c\u0435\u0442\u043e\u0434\u0438\u0447\u0435\u0441\u043a\u043e\u043c \u0434\u043e\u043a\u0443\u043c\u0435\u043d\u0442\u0435 \u0424\u0421\u0422\u042d\u041a \u0420\u043e\u0441\u0441\u0438\u0438, \u0443\u0442\u0432\u0435\u0440\u0436\u0434\u0451\u043d\u043d\u043e\u043c 25 \u0434\u0435\u043a\u0430\u0431\u0440\u044f 2022 \u0433\u043e\u0434\u0430.\n\n\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 Kerberos:\nhttps://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f\n\n\u0414\u043b\u044f Debian GNU/Linux:\nhttps://security-tracker.debian.org/tracker/CVE-2026-40355\nhttps://deb.freexian.com/extended-lts/tracker/CVE-2026-40355\n\n\u0414\u043b\u044f \u041e\u0421 Astra Linux:\n\u043e\u0431\u043d\u043e\u0432\u0438\u0442\u044c \u043f\u0430\u043a\u0435\u0442 krb5 \u0434\u043e 1.19.2-2ubuntu0.7astra7 \u0438\u043b\u0438 \u0431\u043e\u043b\u0435\u0435 \u0432\u044b\u0441\u043e\u043a\u043e\u0439 \u0432\u0435\u0440\u0441\u0438\u0438: https://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17\n\n\u0414\u043b\u044f Ubuntu:\nhttps://ubuntu.com/security/CVE-2026-40355\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-2026-40355",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "13.04.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "28.08.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "28.08.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-12847",
  "\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-2026-40355",
  "\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, Debian GNU/Linux, 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), Red Hat OpenShift Container Platform, Ubuntu, Red Hat Discovery, Red Hat Update Infrastructure, Red Hat Insights proxy, Kerberos",
  "\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 7 , Red Hat, Inc. Red Hat Enterprise Linux 8 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 11 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 12 , \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), Canonical Ltd. Ubuntu 22.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 9 , Canonical Ltd. Ubuntu 24.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 10 , \u0421\u043e\u043e\u0431\u0449\u0435\u0441\u0442\u0432\u043e \u0441\u0432\u043e\u0431\u043e\u0434\u043d\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f Debian GNU/Linux 13 , Canonical Ltd. Ubuntu 26.04 LTS ",
  "\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\u0435\u0442\u0435\u0432\u043e\u0433\u043e \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 \u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u0438 Kerberos, \u0441\u0432\u044f\u0437\u0430\u043d\u043d\u0430\u044f \u0441 \u043e\u0448\u0438\u0431\u043a\u0430\u043c\u0438 \u0440\u0430\u0437\u044b\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u044f \u0443\u043a\u0430\u0437\u0430\u0442\u0435\u043b\u044f, \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": "\u0420\u0430\u0437\u044b\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u043a\u0430\u0437\u0430\u0442\u0435\u043b\u044f NULL (CWE-476)",
  "\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\u0435\u0442\u0435\u0432\u043e\u0433\u043e \u043f\u0440\u043e\u0442\u043e\u043a\u043e\u043b\u0430 \u0430\u0443\u0442\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0446\u0438\u0438 Kerberos \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043e\u0448\u0438\u0431\u043a\u0430\u043c\u0438 \u0440\u0430\u0437\u044b\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u044f \u0443\u043a\u0430\u0437\u0430\u0442\u0435\u043b\u044f. \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": "\u0418\u0441\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u044c: Cem Onat Karagun",
  "\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": "\u041c\u0430\u043d\u0438\u043f\u0443\u043b\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0442\u0440\u0443\u043a\u0442\u0443\u0440\u0430\u043c\u0438 \u0434\u0430\u043d\u043d\u044b\u0445",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://nvd.nist.gov/vuln/detail/CVE-2026-40355\nhttps://security-tracker.debian.org/tracker/CVE-2026-40355\nhttps://github.com/krb5/krb5/commit/2e75f0d9362fb979f5fc92829431a590a130929f\nhttps://web.mit.edu/kerberos/advisories/\nhttps://wiki.astralinux.ru/astra-linux-se17-bulletin-2026-0820SE17\nhttps://deb.freexian.com/extended-lts/tracker/CVE-2026-40355\nhttps://ubuntu.com/security/CVE-2026-40355\nhttps://access.redhat.com/security/cve/CVE-2026-40355",
  "\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, \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-476",
  "\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": "\u0421\u0440\u0435\u0434\u043d\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 5,4)\n\u0421\u0440\u0435\u0434\u043d\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 5,9)"
}

CVE-2026-40355 (GCVE-0-2026-40355)

Vulnerability from cvelistv5 – Published: 2026-04-28 00:00 – Updated: 2026-09-08 08:48

Summary

In MIT Kerberos 5 (aka krb5) before 1.22.3, there is a NULL pointer dereference if an application calls gss_accept_sec_context() on a system with a NegoEx mechanism registered in /etc/gss/mech. An unauthenticated remote attacker can trigger this, causing the process to terminate in parse_nego_message.

Severity

5.9 (Medium)


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

SSVC

Exploitation: poc Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-28 12:53 UTC

CWE

CWE-476 - NULL Pointer Dereference

Assigner

mitre mitre root

References

5 references

URL	Tags
https://web.mit.edu/kerberos/advisories/
https://cems.fun/2026/04/27/krb5-two-unauthentica…
https://github.com/krb5/krb5/commit/2e75f0d9362fb…
https://cert-portal.siemens.com/productcert/html/…
https://cert-portal.siemens.com/productcert/html/…

Impacted products

7 products

Vendor	Product	Version
MIT	Kerberos 5	Affected: 1.18 , < 1.22.3 (custom) cpe:2.3:a:mit:kerberos_5::::::::
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.6 , < * (custom)
Siemens	SIPLUS S7-1500 CPU 1518-4 PN/DP MFP	Affected: V3.1.5 , < * (custom)

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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.