Vulnerability-Lookup

BDU:2026-00006 (CVE-2026-21428)

Vulnerability from fstec – Published: 2026-01-03 – Updated: 2026-01-03 – View on bdu.fstec.ru Exploit publicly available Fixed

Title

Уязвимость функции write_headers() библиотеки cpp-httplib, позволяющая нарушителю модифицировать защищаемую информацию

Summary

Уязвимость функции write_headers() библиотеки cpp-httplib связана с непринятием мер по нейтрализации последовательностей CRLF. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, модифицировать защищаемую информацию путем отправки специально сформированного HTTP-запроса

Severity

7.8 (High) CVSS 2.0


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

7.5 (High) CVSS 3.1


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

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Injection

Incidents

Being clarified

Remediation

Software update

CWE

CWE-93 - Непринятие мер по нейтрализации последовательностей CRLF (Внедрение CRLF)

Aliases

CVE-2026-21428

References

2 references

URL
https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0
https://github.com/yhirose/cpp-httplib/security/advisories/GHSA-wpc6-j37r-jcx7

Impacted products

1 product from 1 vendor

Vendors

Сообщество свободного программного обеспечения

Products

cpp-httplib

Versions

до 0.30.0 (cpp-httplib)

Product types

Network software

Mitigations

Установка обновлений из доверенных источников. В связи со сложившейся обстановкой и введенными санкциями против Российской Федерации рекомендуется устанавливать обновления программного обеспечения только после оценки всех сопутствующих рисков. Компенсирующие меры: - использование средств межсетевого экранирования уровня веб-приложений (WAF) для фильтрации HTTP-запросов; - ограничение доступа к уязвимому программному обеспечению, используя схему доступа по «белым спискам»; - использование систем обнаружения и предотвращения вторжений для обнаружения (выявления, регистрации) и реагирования на попытки эксплуатации уязвимостей; - ограничение доступа из внешних сетей (Интернет); - использование виртуальных частных сетей для организации удаленного доступа (VPN). Использование рекомендаций: https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:N/C:N/I:C/A:N",
  "CVSS 3.0": "AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
  "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": "\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",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "\u0434\u043e 0.30.0 (cpp-httplib)",
  "\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": "\u0423\u0441\u0442\u0430\u043d\u043e\u0432\u043a\u0430 \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0439 \u0438\u0437 \u0434\u043e\u0432\u0435\u0440\u0435\u043d\u043d\u044b\u0445 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u043e\u0432. \u0412 \u0441\u0432\u044f\u0437\u0438 \u0441\u043e \u0441\u043b\u043e\u0436\u0438\u0432\u0448\u0435\u0439\u0441\u044f \u043e\u0431\u0441\u0442\u0430\u043d\u043e\u0432\u043a\u043e\u0439 \u0438 \u0432\u0432\u0435\u0434\u0435\u043d\u043d\u044b\u043c\u0438 \u0441\u0430\u043d\u043a\u0446\u0438\u044f\u043c\u0438 \u043f\u0440\u043e\u0442\u0438\u0432 \u0420\u043e\u0441\u0441\u0438\u0439\u0441\u043a\u043e\u0439 \u0424\u0435\u0434\u0435\u0440\u0430\u0446\u0438\u0438 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0443\u0435\u0442\u0441\u044f \u0443\u0441\u0442\u0430\u043d\u0430\u0432\u043b\u0438\u0432\u0430\u0442\u044c \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f \u0442\u043e\u043b\u044c\u043a\u043e \u043f\u043e\u0441\u043b\u0435 \u043e\u0446\u0435\u043d\u043a\u0438 \u0432\u0441\u0435\u0445 \u0441\u043e\u043f\u0443\u0442\u0441\u0442\u0432\u0443\u044e\u0449\u0438\u0445 \u0440\u0438\u0441\u043a\u043e\u0432.\n\n\u041a\u043e\u043c\u043f\u0435\u043d\u0441\u0438\u0440\u0443\u044e\u0449\u0438\u0435 \u043c\u0435\u0440\u044b:\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0440\u0435\u0434\u0441\u0442\u0432 \u043c\u0435\u0436\u0441\u0435\u0442\u0435\u0432\u043e\u0433\u043e \u044d\u043a\u0440\u0430\u043d\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u0443\u0440\u043e\u0432\u043d\u044f \u0432\u0435\u0431-\u043f\u0440\u0438\u043b\u043e\u0436\u0435\u043d\u0438\u0439 (WAF) \u0434\u043b\u044f \u0444\u0438\u043b\u044c\u0442\u0440\u0430\u0446\u0438\u0438 HTTP-\u0437\u0430\u043f\u0440\u043e\u0441\u043e\u0432;\n- \u043e\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u0438\u0435 \u0434\u043e\u0441\u0442\u0443\u043f\u0430 \u043a \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u043c\u0443 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u043c\u0443 \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044e, \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u0443\u044f \u0441\u0445\u0435\u043c\u0443 \u0434\u043e\u0441\u0442\u0443\u043f\u0430 \u043f\u043e \u00ab\u0431\u0435\u043b\u044b\u043c \u0441\u043f\u0438\u0441\u043a\u0430\u043c\u00bb;\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u0431\u043d\u0430\u0440\u0443\u0436\u0435\u043d\u0438\u044f \u0438 \u043f\u0440\u0435\u0434\u043e\u0442\u0432\u0440\u0430\u0449\u0435\u043d\u0438\u044f \u0432\u0442\u043e\u0440\u0436\u0435\u043d\u0438\u0439 \u0434\u043b\u044f \u043e\u0431\u043d\u0430\u0440\u0443\u0436\u0435\u043d\u0438\u044f (\u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f, \u0440\u0435\u0433\u0438\u0441\u0442\u0440\u0430\u0446\u0438\u0438) \u0438 \u0440\u0435\u0430\u0433\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f \u043d\u0430 \u043f\u043e\u043f\u044b\u0442\u043a\u0438 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0435\u0439;\n- \u043e\u0433\u0440\u0430\u043d\u0438\u0447\u0435\u043d\u0438\u0435 \u0434\u043e\u0441\u0442\u0443\u043f\u0430 \u0438\u0437 \u0432\u043d\u0435\u0448\u043d\u0438\u0445 \u0441\u0435\u0442\u0435\u0439 (\u0418\u043d\u0442\u0435\u0440\u043d\u0435\u0442);\n- \u0438\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0432\u0438\u0440\u0442\u0443\u0430\u043b\u044c\u043d\u044b\u0445 \u0447\u0430\u0441\u0442\u043d\u044b\u0445 \u0441\u0435\u0442\u0435\u0439 \u0434\u043b\u044f \u043e\u0440\u0433\u0430\u043d\u0438\u0437\u0430\u0446\u0438\u0438 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e\u0433\u043e \u0434\u043e\u0441\u0442\u0443\u043f\u0430 (VPN).\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:\nhttps://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "01.01.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "03.01.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "03.01.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-00006",
  "\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-2026-21428",
  "\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": "cpp-httplib",
  "\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": null,
  "\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 \u0444\u0443\u043d\u043a\u0446\u0438\u0438 write_headers() \u0431\u0438\u0431\u043b\u0438\u043e\u0442\u0435\u043a\u0438 cpp-httplib, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u043c\u043e\u0434\u0438\u0444\u0438\u0446\u0438\u0440\u043e\u0432\u0430\u0442\u044c \u0437\u0430\u0449\u0438\u0449\u0430\u0435\u043c\u0443\u044e \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044e",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0421\u0443\u0449\u0435\u0441\u0442\u0432\u0443\u0435\u0442 \u0432 \u043e\u0442\u043a\u0440\u044b\u0442\u043e\u043c \u0434\u043e\u0441\u0442\u0443\u043f\u0435",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u043f\u0440\u0438\u043d\u044f\u0442\u0438\u0435 \u043c\u0435\u0440 \u043f\u043e \u043d\u0435\u0439\u0442\u0440\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u043f\u043e\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u043d\u043e\u0441\u0442\u0435\u0439 CRLF (\u0412\u043d\u0435\u0434\u0440\u0435\u043d\u0438\u0435 CRLF) (CWE-93)",
  "\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 \u0444\u0443\u043d\u043a\u0446\u0438\u0438 write_headers() \u0431\u0438\u0431\u043b\u0438\u043e\u0442\u0435\u043a\u0438 cpp-httplib \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u043f\u0440\u0438\u043d\u044f\u0442\u0438\u0435\u043c \u043c\u0435\u0440 \u043f\u043e \u043d\u0435\u0439\u0442\u0440\u0430\u043b\u0438\u0437\u0430\u0446\u0438\u0438 \u043f\u043e\u0441\u043b\u0435\u0434\u043e\u0432\u0430\u0442\u0435\u043b\u044c\u043d\u043e\u0441\u0442\u0435\u0439 CRLF. \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, \u043c\u043e\u0434\u0438\u0444\u0438\u0446\u0438\u0440\u043e\u0432\u0430\u0442\u044c \u0437\u0430\u0449\u0438\u0449\u0430\u0435\u043c\u0443\u044e \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044e \u043f\u0443\u0442\u0435\u043c \u043e\u0442\u043f\u0440\u0430\u0432\u043a\u0438 \u0441\u043f\u0435\u0446\u0438\u0430\u043b\u044c\u043d\u043e \u0441\u0444\u043e\u0440\u043c\u0438\u0440\u043e\u0432\u0430\u043d\u043d\u043e\u0433\u043e HTTP-\u0437\u0430\u043f\u0440\u043e\u0441\u0430",
  "\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\u043d\u044a\u0435\u043a\u0446\u0438\u044f",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://github.com/yhirose/cpp-httplib/releases/tag/v0.30.0\nhttps://github.com/yhirose/cpp-httplib/security/advisories/GHSA-wpc6-j37r-jcx7",
  "\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": "\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",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-93",
  "\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-2026-21428 (GCVE-0-2026-21428)

Vulnerability from cvelistv5 – Published: 2026-01-01 17:54 – Updated: 2026-01-02 18:50

Title

cpp-httplib has CRLF injection in http headers

Summary

cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR & LF characters in user supplied headers, allowing untrusted header value to escape header lines. This vulnerability allows attackers to add extra headers, modify request body unexpectedly & trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue.

Severity

7.7 (High)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P

SSVC

Exploitation: poc Automatable: yes Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-01-02 18:50 UTC

CWE

CWE-93 - Improper Neutralization of CRLF Sequences ('CRLF Injection')

Assigner

GitHub_M mitre root

References

3 references

URL	Tags
https://github.com/yhirose/cpp-httplib/security/a…	x_refsource_CONFIRM
https://github.com/yhirose/cpp-httplib/commit/980…	x_refsource_MISC
https://github.com/yhirose/cpp-httplib/releases/t…	x_refsource_MISC

Impacted products

1 product

Vendor	Product	Version
yhirose	cpp-httplib	Affected: < 0.30.0

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-21428",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-01-02T18:50:07.704892Z",
                "version": "2.0.3"
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          "shortName": "CISA-ADP"
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    "cna": {
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        {
          "product": "cpp-httplib",
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          "versions": [
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          "lang": "en",
          "value": "cpp-httplib is a C++11 single-file header-only cross platform HTTP/HTTPS library. Prior to version 0.30.0, the ``write_headers`` function does not check for CR \u0026 LF characters in user supplied headers, allowing untrusted header value to escape header lines.\nThis vulnerability allows attackers to add extra headers, modify request body unexpectedly \u0026 trigger an SSRF attack. When combined with a server that supports http1.1 pipelining (springboot, python twisted etc), this can be used for server side request forgery (SSRF). Version 0.30.0 fixes this issue."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "LOW",
            "attackRequirements": "NONE",
            "attackVector": "NETWORK",
            "baseScore": 7.7,
            "baseSeverity": "HIGH",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:P",
            "version": "4.0",
            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "HIGH"
          }
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      ],
      "problemTypes": [
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          "descriptions": [
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              "cweId": "CWE-93",
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    "dateReserved": "2025-12-29T03:00:29.274Z",
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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.