Red Hat Security Advisory: python3.9 security update
Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems. Security Fix(es): * cpython: wsgiref.headers.Headers allows header newline injection in Python (CVE-2026-0865) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Additional Changes: For detailed information on changes in this release, see the Red Hat Enterprise Linux 9 Release Notes linked from the References section.
AI Analysis
Technical Summary
The vulnerability CVE-2026-0865 involves the cpython wsgiref.headers.Headers class, which allows header newline injection in Python. This can potentially allow injection of newline characters into HTTP headers, which is classified under CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component). Red Hat has issued a security advisory (RHSA-2026:18693) for this issue affecting Python 3.9 packages in Red Hat Enterprise Linux 9 and related products. The advisory rates the severity as moderate and provides updated packages to remediate the issue.
Potential Impact
The vulnerability allows injection of newline characters into HTTP headers via the wsgiref.headers.Headers class in Python. This could lead to HTTP response splitting or related injection issues. Red Hat rates the impact as moderate. There are no known exploits in the wild reported at this time.
Mitigation Recommendations
Red Hat has released security updates for Python 3.9 packages in Red Hat Enterprise Linux 9 and related variants to address CVE-2026-0865. Users should apply the available updates as described in the Red Hat advisory (RHSA-2026:18693) and the referenced update article (https://access.redhat.com/articles/11258). Patch status is confirmed as available. No additional mitigation steps are specified by the vendor.
Red Hat Security Advisory: python3.9 security update
Description
Python is an interpreted, interactive, object-oriented programming language, which includes modules, classes, exceptions, very high level dynamic data types and dynamic typing. Python supports interfaces to many system calls and libraries, as well as to various windowing systems. Security Fix(es): * cpython: wsgiref.headers.Headers allows header newline injection in Python (CVE-2026-0865) For more details about the security issue(s), including the impact, a CVSS score, acknowledgments, and other related information, refer to the CVE page(s) listed in the References section. Additional Changes: For detailed information on changes in this release, see the Red Hat Enterprise Linux 9 Release Notes linked from the References section.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-0865 involves the cpython wsgiref.headers.Headers class, which allows header newline injection in Python. This can potentially allow injection of newline characters into HTTP headers, which is classified under CWE-74 (Improper Neutralization of Special Elements in Output Used by a Downstream Component). Red Hat has issued a security advisory (RHSA-2026:18693) for this issue affecting Python 3.9 packages in Red Hat Enterprise Linux 9 and related products. The advisory rates the severity as moderate and provides updated packages to remediate the issue.
Potential Impact
The vulnerability allows injection of newline characters into HTTP headers via the wsgiref.headers.Headers class in Python. This could lead to HTTP response splitting or related injection issues. Red Hat rates the impact as moderate. There are no known exploits in the wild reported at this time.
Mitigation Recommendations
Red Hat has released security updates for Python 3.9 packages in Red Hat Enterprise Linux 9 and related variants to address CVE-2026-0865. Users should apply the available updates as described in the Red Hat advisory (RHSA-2026:18693) and the referenced update article (https://access.redhat.com/articles/11258). Patch status is confirmed as available. No additional mitigation steps are specified by the vendor.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:18958
- Cve Count
- 1
- Additional Cves
- []
- Cvss Version
- null
Threat ID: 6a175eeee29bf47b50edcf16
Added to database: 05/27/2026, 21:15:26 UTC
Last enriched: 07/04/2026, 01:53:38 UTC
Last updated: 07/31/2026, 19:22:57 UTC
Views: 72
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