CVE-2025-9232

Out-of-bounds read in HTTP client no_proxy handling

At a glance

Severity
MEDIUM 5.9
EPSS
EPSS 2.00 % · percentile 81 (2026-10-27)
State
PUBLISHED
Published
Updated
Assigner
openssl
NVD status
Deferred

Description

Issue summary: An application using the OpenSSL HTTP client API functions may trigger an out-of-bounds read if the 'no_proxy' environment variable is set and the host portion of the authority component of the HTTP URL is an IPv6 address. Impact summary: An out-of-bounds read can trigger a crash which leads to Denial of Service for an application. The OpenSSL HTTP client API functions can be used directly by applications but they are also used by the OCSP client functions and CMP (Certificate Management Protocol) client implementation in OpenSSL. However the URLs used by these implementations are unlikely to be controlled by an attacker. In this vulnerable code the out of bounds read can only trigger a crash. Furthermore the vulnerability requires an attacker-controlled URL to be passed from an application to the OpenSSL function and the user has to have a 'no_proxy' environment variable set. For the aforementioned reasons the issue was assessed as Low severity. The vulnerable code was introduced in the following patch releases: 3.0.16, 3.1.8, 3.2.4, 3.3.3, 3.4.0 and 3.5.0. The FIPS modules in 3.5, 3.4, 3.3, 3.2, 3.1 and 3.0 are not affected by this issue, as the HTTP client implementation is outside the OpenSSL FIPS module boundary.

Scores

VersionScoreVectorScored by
CVSS 3.1MEDIUM 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HCISA-ADP
CVSS 3.1MEDIUM 5.9CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:HNVD · 134c704f-9b21-4f2e-91b3-4a467353bcc0 (Secondary)

Weaknesses (CWE)

European references

CERT-FR advisories

Affected products

ProductVersions
OpenSSL · OpenSSLaffected 3.5.0 < 3.5.4 ; affected 3.4.0 < 3.4.3 ; affected 3.3.3 < 3.3.5 ; affected 3.2.4 < 3.2.6 ; affected 3.0.16 < 3.0.18

References

Sources

SourceLicence
CVE List (CVEProject cvelistV5)CVE Program Terms of Use
EPSS (FIRST.org)FIRST — attribution requested
ENISA EUVDENISA — reproduction authorised, source acknowledged
CERT-FR (ANSSI)Licence Ouverte / Etalab 2.0
NVD (NIST) via fkie-cad/nvd-json-data-feedsPublic domain — this product uses data from the NVD API but is not endorsed or certified by the NVD