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CVE-2023-35941

25
FAUCET Score

CVE-2023-35941 is a critical vulnerability affecting Envoy proxy versions prior to 1.27.0, 1.26.4, 1.25.9, 1.24.10, and 1.23.12. A malicious client can craft credentials with permanent validity due to a flaw in the OAuth2 filter's HMAC payload check. This vulnerability carries a CVSS score of 9.8 (Critical), indicating it can be exploited remotely with low complexity, leading to high impact on confidentiality, integrity, and availability. While there is no evidence of active exploitation, exploit code, or significant community discussion, a workaround involves avoiding wildcards in host domain configurations.

Impacted Technologies

VendorProductVersion(s)CPE
>= 1.23.0, < 1.23.12CPE matchmatch criteria
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
>= 1.24.0, < 1.24.10CPE matchmatch criteria
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
>= 1.25.0, < 1.25.9CPE matchmatch criteria
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*
>= 1.26.0, < 1.26.4CPE matchmatch criteria
cpe:2.3:a:envoyproxy:envoy:*:*:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 3.1

8.6HIGH

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

Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality Impact
HIGH
Integrity Impact
LOW
Availability Impact
LOW
Exploitability Score
3.9
Impact Score
4.7
CvssVersion
3.1

Exploit Intelligence

EPSS Score
0.81%
Probability of exploitation in next 30 days
EPSS Percentile
53.3%
Percentile rank of EPSS score among Peer Group
As of 2026-07-27
Model: v2026.06.15
This CVE's current EPSS score of 0.0081 is in the 37th percentile among its peer group of 36,897 CVEs.

Social Chatter

The average CVE in this peer group has 0.0 Twitter, 0.1 Reddit, 0.3 Bluesky, 0.3 Mastodon, and 2.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.3 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Patch Available

Vendor Patches (3)

redhatpatch availablevia redhat_api
Product: Red Hat OpenShift Service Mesh 2.2 for RHEL 8Fixed in: openshift-service-mesh/proxyv2-rhel8:2.2.10-3
View patch
redhatpatch availablevia redhat_api
Product: Red Hat OpenShift Service Mesh 2.3 for RHEL 8Fixed in: openshift-service-mesh/proxyv2-rhel8:2.3.6-4
View patch
redhatpatch availablevia redhat_api
Product: Red Hat OpenShift Service Mesh 2.4 for RHEL 8Fixed in: openshift-service-mesh/proxyv2-rhel8:2.4.2-7
View patch

Vendor Advisories (1)

redhatCVE-2023-35941Important

envoy: OAuth2 credentials exploit with permanent validity

Jul 25, 2023

References

github.com / envoyproxy/envoy/security/advisories/GHSA-7mhv-gr67-hq55
Third Party Advisory