Red Hat Security Advisory: python3.9 security update
A moderate severity security vulnerability (CVE-2025-0938) was identified in the Python 3 URL parser used in Red Hat Enterprise Linux 8. The flaw allowed square brackets in domain names, which is not standard behavior. This issue affects multiple Python 3 versions distributed with Red Hat Enterprise Linux 8 across various architectures. Red Hat has issued a security advisory (RHSA-2026:5588) with updated packages to address this vulnerability.
AI Analysis
Technical Summary
The vulnerability CVE-2025-0938 affects the python3.9 package in Red Hat Enterprise Linux 9. The flaw is in the CPython URL parser component, which incorrectly allowed square brackets in domain names. This behavior could lead to improper validation of URLs. Red Hat has issued a security advisory (RHSA-2025:6977) providing an updated python3.9 package that fixes this issue. The advisory rates the impact as moderate and provides detailed instructions for applying the update. No CVSS score is provided in the advisory. The vulnerability is tracked under CWE-20 (Improper Input Validation).
Potential Impact
The vulnerability allows the URL parser in python3.9 to accept square brackets in domain names, which is not standard and could potentially lead to improper handling of URLs by applications relying on this parser. The advisory classifies the security impact as moderate. There are no known exploits in the wild reported at this time.
Mitigation Recommendations
Red Hat has released an official security update for python3.9 in Red Hat Enterprise Linux 9 that addresses this vulnerability. Users should apply the update following the instructions in the Red Hat advisory (https://access.redhat.com/articles/11258). Since an official fix is available, applying the update is the recommended remediation. No additional mitigation steps are indicated by the vendor.
Red Hat Security Advisory: python3.9 security update
Description
A moderate severity security vulnerability (CVE-2025-0938) was identified in the Python 3 URL parser used in Red Hat Enterprise Linux 8. The flaw allowed square brackets in domain names, which is not standard behavior. This issue affects multiple Python 3 versions distributed with Red Hat Enterprise Linux 8 across various architectures. Red Hat has issued a security advisory (RHSA-2026:5588) with updated packages to address this vulnerability.
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2025-0938 affects the python3.9 package in Red Hat Enterprise Linux 9. The flaw is in the CPython URL parser component, which incorrectly allowed square brackets in domain names. This behavior could lead to improper validation of URLs. Red Hat has issued a security advisory (RHSA-2025:6977) providing an updated python3.9 package that fixes this issue. The advisory rates the impact as moderate and provides detailed instructions for applying the update. No CVSS score is provided in the advisory. The vulnerability is tracked under CWE-20 (Improper Input Validation).
Potential Impact
The vulnerability allows the URL parser in python3.9 to accept square brackets in domain names, which is not standard and could potentially lead to improper handling of URLs by applications relying on this parser. The advisory classifies the security impact as moderate. There are no known exploits in the wild reported at this time.
Mitigation Recommendations
Red Hat has released an official security update for python3.9 in Red Hat Enterprise Linux 9 that addresses this vulnerability. Users should apply the update following the instructions in the Red Hat advisory (https://access.redhat.com/articles/11258). Since an official fix is available, applying the update is the recommended remediation. No additional mitigation steps are indicated 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-2026:5588
- Cve Count
- 1
Threat ID: 6a3da1c14853345fc181dd26
Added to database: 06/25/2026, 21:46:41 UTC
Last enriched: 08/18/2026, 14:13:34 UTC
Last updated: 09/10/2026, 19:36:49 UTC
Views: 32
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