CVE-2023-27491

criticalpriority · track · 36EPSS 0.009 · 59 %ileDEEUUS
grimoire priorityP2 · Scheduled
Exploitable?
—
no known exploitation
Likely / severe?
0.87% (59th) EPSS
CVSS 9.1 · critical
Is it mine?
37 products
Check your exposure
Who says so?
6 sources
cnnvd · enisa_euvd · osv · cert_bund

EPSS · scored 2026-10-27

Envoy is an open source edge and service proxy designed for cloud-native applications. Compliant HTTP/1 service should reject malformed request lines. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, There is a possibility that non compliant HTTP/1 service may allow malformed requests, potentially leading to a bypass of security policies. This issue is fixed in versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • Fixedopenshift-service-mesh/proxyv2-rhel8@sha256:29246b072bb2829c8e86b41e7ecdf8e3845d64b9f87247cf81a6088a3d040d3c_ppc64le as a component of RHOSSM 2.2 for RHEL 8redhat_csaf

    Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258

    https://access.redhat.com/errata/RHSA-2023:4623
  • Fixedopenshift-service-mesh/proxyv2-rhel8@sha256:60036f920ef18e80ed97dadb25e4d6ae2e63f74e04c51e18badf22aae25a7f50_s390x as a component of RHOSSM 2.2 for RHEL 8redhat_csaf

    Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258

    https://access.redhat.com/errata/RHSA-2023:4623
  • Fixedopenshift-service-mesh/proxyv2-rhel8@sha256:d8a8d11de42f5105b47b89bf715945825fa496d05aa1fcbcbd230bad2d31d59f_amd64 as a component of RHOSSM 2.2 for RHEL 8redhat_csaf

    Before applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258

    https://access.redhat.com/errata/RHSA-2023:4623
02

cvss

Technical severity, 0–10. One row per scoring source.

9.1
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–critical · 5.4–9.1

v3.19.1criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Nprimary · NVD / NIST USexploitability 3.9 · impact 5.2
v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Nsecondary · ENISA EU
v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:Nsecondary · security-advisories@github.comexploitability 2.8 · impact 2.5
v3.18.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N/E:Usecondary · CVSS-BT (t0sche)
v3.16.5mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:Hsecondary · Red Hat Product Security US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: poc · Automatable: no · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-444USprimaryCWE-20USCWE-20US
05

affected products (37)

Products and version ranges known to be affected.

showing 20 of 37
06

advisories (3)

Vendor and ecosystem advisories describing this.

  • RHSA-2023:4623Red Hat Security Advisory: Red Hat OpenShift Service Mesh 2.2.9 security update2023-08-11csaf · redhat_csafUS

    Red Hat OpenShift Service Mesh 2.2.9 Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.

  • WID-SEC-W-2023-2058Red Hat OpenShift Service Mesh und Service Mesh Containers: Mehrere SchwachstellenDeutsch2023-08-13csaf · cert_bundDE

    Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Red Hat OpenShift Service Mesh und Service Mesh Containers, sowie Red Hat Enterprise Linux ausnutzen, um einen Denial of Service Zustand herbeizuführen, Dateien zu manipulieren, Sicherheitsvorkehrungen zu umgehen oder Informationen offenzulegen.

  • BIT-envoy-2023-27491Envoy forwards invalid Http2/Http3 downstream headers2024-03-06vendor · osvUS

    Envoy is an open source edge and service proxy designed for cloud-native applications. Compliant HTTP/1 service should reject malformed request lines. Prior to versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9, There is a possibility that non compliant HTTP/1 service may allow malformed requests, potentially leading to a bypass of security policies. This issue is fixed in versions 1.26.0, 1.25.3, 1.24.4, 1.23.6, and 1.22.9.

07

also known as (3)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdosvcert_bundnvdredhat_csafNVDCVE.orgMITRE
published 2023-04-04modified 2026-06-17
10

references (15)

External citations — patches, advisories, analysis.

scry

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