Vulnerability-Lookup

BDU:2026-07733 (CVE-2026-34831)

Vulnerability from fstec – Published: 2026-06-03 – Updated: 2026-06-19 – View on bdu.fstec.ru Fixed

Title

Уязвимость модульного интерфейса веб-сервера Rack языка программирования Ruby, связанная с неправильной обработкой несоответствия параметра длины, позволяющая нарушителю оказать воздействие на конфиденциальность и целостность защищаемой информации

Summary

Уязвимость модульного интерфейса веб-сервера Rack языка программирования Ruby связана с неправильной обработкой несоответствия параметра длины. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, оказать воздействие на конфиденциальность и целостность защищаемой информации

Severity

6.4 (Medium) CVSS 2.0


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

6.5 (Medium) CVSS 3.1


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

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Data structure manipulation

Incidents

Being clarified

Remediation

Software update

CWE

CWE-130 - Неправильная обработка несоответствия параметра длины
CWE-135 - Неправильный расчет длины многобайтовой строки

Aliases

CVE-2026-34831

References

6 references

URL
https://github.com/rack/rack
https://github.com/rack/rack/security/advisories/GHSA-q2ww-5357-x388
https://redos.red-soft.ru/search/?iblock_id=&q=CVE-2026-34831
https://access.redhat.com/security/cve/cve-2026-34831
https://ubuntu.com/security/CVE-2026-34831
https://altsp.su/obnovleniya-bezopasnosti/

Impacted products

7 products from 6 vendors

Vendors

Canonical Ltd., Red Hat, Inc., ООО «Ред Софт», АО «ИВК», Сообщество свободного программного обеспечения

Products

Ubuntu, Red Hat Enterprise Linux, Red Hat 3scale API Management Platform, РЕД ОС (запись в едином реестре российских программ №3751), АЛЬТ СП 10, Logging subsystem for Red Hat OpenShift, Rack

Versions

14.04 LTS (Ubuntu), 7 (Red Hat Enterprise Linux), 16.04 LTS (Ubuntu), 18.04 LTS (Ubuntu), 8 (Red Hat Enterprise Linux), 20.04 LTS (Ubuntu), 2 (Red Hat 3scale API Management Platform), 7.3 (РЕД ОС), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), - (АЛЬТ СП 10), - (Logging subsystem for Red Hat OpenShift), 24.04 LTS (Ubuntu), 10 (Red Hat Enterprise Linux), 25.10 (Ubuntu), 8.0 (РЕД ОС), 26.04 LTS (Ubuntu), до 2.2.23 (Rack), от 3.0 до 3.1.21 (Rack), от 3.2 до 3.2.6 (Rack)

Product types

Operating system, Application software

Platforms

Canonical Ltd. Ubuntu 14.04 LTS, Red Hat, Inc. Red Hat Enterprise Linux 7, Canonical Ltd. Ubuntu 16.04 LTS, Canonical Ltd. Ubuntu 18.04 LTS, Inc. Red Hat Enterprise Linux 8, Canonical Ltd. Ubuntu 20.04 LTS, ООО «Ред Софт» РЕД ОС 7.3 (запись в едином реестре российских программ №3751), Canonical Ltd. Ubuntu 22.04 LTS, Inc. Red Hat Enterprise Linux 9, АО «ИВК» АЛЬТ СП 10 -, Canonical Ltd. Ubuntu 24.04 LTS, Inc. Red Hat Enterprise Linux 10, Canonical Ltd. Ubuntu 25.10, ООО «Ред Софт» РЕД ОС 8.0 (запись в едином реестре российских программ №3751), Canonical Ltd. Ubuntu 26.04 LTS

Mitigations

Использование рекомендаций: Для Rack: https://github.com/rack/rack/security/advisories/GHSA-q2ww-5357-x388 Для Ред ОС: https://redos.red-soft.ru/search/?iblock_id=&q=CVE-2026-34831 Для Ubuntu: https://ubuntu.com/security/CVE-2026-34831 Для программных продуктов Red Hat Inc.: https://access.redhat.com/security/cve/cve-2026-34831 Для ОС АЛЬТ СП 10: установка обновления из публичного репозитория программного средства: https://altsp.su/obnovleniya-bezopasnosti/

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:N/C:P/I:P/A:N",
  "CVSS 3.0": "AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/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": "Canonical Ltd., Red Hat, Inc., \u041e\u041e\u041e \u00ab\u0420\u0435\u0434 \u0421\u043e\u0444\u0442\u00bb, \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb, \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": "14.04 LTS (Ubuntu), 7 (Red Hat Enterprise Linux), 16.04 LTS (Ubuntu), 18.04 LTS (Ubuntu), 8 (Red Hat Enterprise Linux), 20.04 LTS (Ubuntu), 2 (Red Hat 3scale API Management Platform), 7.3 (\u0420\u0415\u0414 \u041e\u0421), 22.04 LTS (Ubuntu), 9 (Red Hat Enterprise Linux), - (\u0410\u041b\u042c\u0422 \u0421\u041f 10), - (Logging subsystem for Red Hat OpenShift), 24.04 LTS (Ubuntu), 10 (Red Hat Enterprise Linux), 25.10 (Ubuntu), 8.0 (\u0420\u0415\u0414 \u041e\u0421), 26.04 LTS (Ubuntu), \u0434\u043e 2.2.23 (Rack), \u043e\u0442 3.0 \u0434\u043e 3.1.21 (Rack), \u043e\u0442 3.2 \u0434\u043e 3.2.6 (Rack)",
  "\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 Rack:\nhttps://github.com/rack/rack/security/advisories/GHSA-q2ww-5357-x388\n\n\u0414\u043b\u044f \u0420\u0435\u0434 \u041e\u0421:\nhttps://redos.red-soft.ru/search/?iblock_id=\u0026q=CVE-2026-34831\n\n\u0414\u043b\u044f Ubuntu:\nhttps://ubuntu.com/security/CVE-2026-34831\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-2026-34831\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/",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "02.04.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "19.06.2026",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "03.06.2026",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2026-07733",
  "\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-2026-34831",
  "\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": "Ubuntu, Red Hat Enterprise Linux, Red Hat 3scale API Management Platform, \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), \u0410\u041b\u042c\u0422 \u0421\u041f 10, Logging subsystem for Red Hat OpenShift, Rack",
  "\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": "Canonical Ltd. Ubuntu 14.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 7 , Canonical Ltd. Ubuntu 16.04 LTS , Canonical Ltd. Ubuntu 18.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 8 , Canonical Ltd. Ubuntu 20.04 LTS , \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), Canonical Ltd. Ubuntu 22.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 9 , \u0410\u041e \u00ab\u0418\u0412\u041a\u00bb \u0410\u041b\u042c\u0422 \u0421\u041f 10 - , Canonical Ltd. Ubuntu 24.04 LTS , Red Hat, Inc. Red Hat Enterprise Linux 10 , Canonical Ltd. Ubuntu 25.10 , \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), 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 \u043c\u043e\u0434\u0443\u043b\u044c\u043d\u043e\u0433\u043e \u0438\u043d\u0442\u0435\u0440\u0444\u0435\u0439\u0441\u0430 \u0432\u0435\u0431-\u0441\u0435\u0440\u0432\u0435\u0440\u0430 Rack \u044f\u0437\u044b\u043a\u0430 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f Ruby, \u0441\u0432\u044f\u0437\u0430\u043d\u043d\u0430\u044f \u0441 \u043d\u0435\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u043e\u0439 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u043e\u0439 \u043d\u0435\u0441\u043e\u043e\u0442\u0432\u0435\u0442\u0441\u0442\u0432\u0438\u044f \u043f\u0430\u0440\u0430\u043c\u0435\u0442\u0440\u0430 \u0434\u043b\u0438\u043d\u044b, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u043e\u043a\u0430\u0437\u0430\u0442\u044c \u0432\u043e\u0437\u0434\u0435\u0439\u0441\u0442\u0432\u0438\u0435 \u043d\u0430 \u043a\u043e\u043d\u0444\u0438\u0434\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e\u0441\u0442\u044c \u0438 \u0446\u0435\u043b\u043e\u0441\u0442\u043d\u043e\u0441\u0442\u044c \u0437\u0430\u0449\u0438\u0449\u0430\u0435\u043c\u043e\u0439 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\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\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u0430\u044f \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0430 \u043d\u0435\u0441\u043e\u043e\u0442\u0432\u0435\u0442\u0441\u0442\u0432\u0438\u044f \u043f\u0430\u0440\u0430\u043c\u0435\u0442\u0440\u0430 \u0434\u043b\u0438\u043d\u044b (CWE-130), \u041d\u0435\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u044b\u0439 \u0440\u0430\u0441\u0447\u0435\u0442 \u0434\u043b\u0438\u043d\u044b \u043c\u043d\u043e\u0433\u043e\u0431\u0430\u0439\u0442\u043e\u0432\u043e\u0439 \u0441\u0442\u0440\u043e\u043a\u0438 (CWE-135)",
  "\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 \u043c\u043e\u0434\u0443\u043b\u044c\u043d\u043e\u0433\u043e \u0438\u043d\u0442\u0435\u0440\u0444\u0435\u0439\u0441\u0430 \u0432\u0435\u0431-\u0441\u0435\u0440\u0432\u0435\u0440\u0430 Rack \u044f\u0437\u044b\u043a\u0430 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u0438\u0440\u043e\u0432\u0430\u043d\u0438\u044f Ruby \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u043f\u0440\u0430\u0432\u0438\u043b\u044c\u043d\u043e\u0439 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u043e\u0439 \u043d\u0435\u0441\u043e\u043e\u0442\u0432\u0435\u0442\u0441\u0442\u0432\u0438\u044f \u043f\u0430\u0440\u0430\u043c\u0435\u0442\u0440\u0430 \u0434\u043b\u0438\u043d\u044b. \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, \u043e\u043a\u0430\u0437\u0430\u0442\u044c \u0432\u043e\u0437\u0434\u0435\u0439\u0441\u0442\u0432\u0438\u0435 \u043d\u0430 \u043a\u043e\u043d\u0444\u0438\u0434\u0435\u043d\u0446\u0438\u0430\u043b\u044c\u043d\u043e\u0441\u0442\u044c \u0438 \u0446\u0435\u043b\u043e\u0441\u0442\u043d\u043e\u0441\u0442\u044c \u0437\u0430\u0449\u0438\u0449\u0430\u0435\u043c\u043e\u0439 \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\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": "\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://github.com/rack/rack\nhttps://github.com/rack/rack/security/advisories/GHSA-q2ww-5357-x388\nhttps://redos.red-soft.ru/search/?iblock_id=\u0026q=CVE-2026-34831\nhttps://access.redhat.com/security/cve/cve-2026-34831\nhttps://ubuntu.com/security/CVE-2026-34831\nhttps://altsp.su/obnovleniya-bezopasnosti/",
  "\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-130, CWE-135",
  "\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 6,4)\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 6,5)"
}

CVE-2026-34831 (GCVE-0-2026-34831)

Vulnerability from cvelistv5 – Published: 2026-04-02 16:43 – Updated: 2026-04-03 17:48

Title

Rack: Content-Length mismatch in Rack::Files error responses

Summary

Rack is a modular Ruby web server interface. Prior to versions 2.2.23, 3.1.21, and 3.2.6, Rack::Files#fail sets the Content-Length response header using String#size instead of String#bytesize. When the response body contains multibyte UTF-8 characters, the declared Content-Length is smaller than the number of bytes actually sent on the wire. Because Rack::Files reflects the requested path in 404 responses, an attacker can trigger this mismatch by requesting a non-existent path containing percent-encoded UTF-8 characters. This results in incorrect HTTP response framing and may cause response desynchronization in deployments that rely on the incorrect Content-Length value. This issue has been patched in versions 2.2.23, 3.1.21, and 3.2.6.

Severity

4.8 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-04-03 17:43 UTC

CWE

CWE-130 - Improper Handling of Length Parameter Inconsistency
CWE-135 - Incorrect Calculation of Multi-Byte String Length

Assigner

GitHub_M mitre root

References

1 reference

URL	Tags
https://github.com/rack/rack/security/advisories/…	x_refsource_CONFIRM

Impacted products

1 product

Vendor	Product	Version
rack	rack	Affected: < 2.2.23 Affected: >= 3.0.0.beta1, < 3.1.21 Affected: >= 3.2.0, < 3.2.6

Show details on NVD website

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                "id": "CVE-2026-34831",
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                "role": "CISA Coordinator",
                "timestamp": "2026-04-03T17:43:52.462237Z",
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            "confidentialityImpact": "LOW",
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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.