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.
Fixes

Solution

No solution given by the vendor.


Workaround

No workaround given by the vendor.

History

Tue, 30 Sep 2025 20:15:00 +0000

Type Values Removed Values Added
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H'}

ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Tue, 30 Sep 2025 13:30:00 +0000

Type Values Removed Values Added
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.
Title Out-of-bounds read in HTTP client no_proxy handling
Weaknesses CWE-125
References

cve-icon MITRE

Status: PUBLISHED

Assigner: openssl

Published:

Updated: 2025-09-30T19:22:35.483Z

Reserved: 2025-08-20T08:38:12.019Z

Link: CVE-2025-9232

cve-icon Vulnrichment

Updated: 2025-09-30T19:22:23.941Z

cve-icon NVD

Status : Received

Published: 2025-09-30T14:15:41.313

Modified: 2025-09-30T20:15:41.397

Link: CVE-2025-9232

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.