Red Hat Security Advisory: python3.12-urllib3 security update
This advisory addresses multiple security vulnerabilities in the python3. 12-urllib3 package for Red Hat Enterprise Linux 9. 4 Extended Update Support. The issues include unbounded decompression chains leading to resource exhaustion, improper handling of highly compressed data in the streaming API, and a decompression-bomb safeguard bypass when following HTTP redirects. These vulnerabilities could potentially allow resource exhaustion attacks via specially crafted compressed data. Red Hat has released updated packages to fix these issues.
AI Analysis
Technical Summary
The python3.12-urllib3 package in Red Hat Enterprise Linux 9.4 Extended Update Support contains three security vulnerabilities: CVE-2025-66418 involves an unbounded decompression chain that can cause resource exhaustion; CVE-2025-66471 concerns improper handling of highly compressed data in the streaming API; and CVE-2026-21441 allows bypassing decompression-bomb safeguards when following HTTP redirects in the streaming API. These issues relate to the handling of compressed data streams and can lead to denial-of-service conditions. Red Hat Product Security has rated the update as Important and has released patched versions of the package to address these vulnerabilities.
Potential Impact
The vulnerabilities can lead to resource exhaustion on affected systems due to unbounded decompression chains or improper handling of compressed data, potentially causing denial-of-service conditions. There are no known exploits in the wild at this time. The issues affect Red Hat Enterprise Linux 9.4 Extended Update Support and related variants using python3.12-urllib3.
Mitigation Recommendations
Red Hat has released updated python3.12-urllib3 packages that address these vulnerabilities. Users of affected Red Hat Enterprise Linux 9.4 Extended Update Support systems should apply the provided security updates as detailed in the Red Hat advisory RHSA-2026:1957 and the referenced article https://access.redhat.com/articles/11258. Applying these updates will remediate the vulnerabilities. No additional mitigation actions are specified by the vendor.
Red Hat Security Advisory: python3.12-urllib3 security update
Description
This advisory addresses multiple security vulnerabilities in the python3. 12-urllib3 package for Red Hat Enterprise Linux 9. 4 Extended Update Support. The issues include unbounded decompression chains leading to resource exhaustion, improper handling of highly compressed data in the streaming API, and a decompression-bomb safeguard bypass when following HTTP redirects. These vulnerabilities could potentially allow resource exhaustion attacks via specially crafted compressed data. Red Hat has released updated packages to fix these issues.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The python3.12-urllib3 package in Red Hat Enterprise Linux 9.4 Extended Update Support contains three security vulnerabilities: CVE-2025-66418 involves an unbounded decompression chain that can cause resource exhaustion; CVE-2025-66471 concerns improper handling of highly compressed data in the streaming API; and CVE-2026-21441 allows bypassing decompression-bomb safeguards when following HTTP redirects in the streaming API. These issues relate to the handling of compressed data streams and can lead to denial-of-service conditions. Red Hat Product Security has rated the update as Important and has released patched versions of the package to address these vulnerabilities.
Potential Impact
The vulnerabilities can lead to resource exhaustion on affected systems due to unbounded decompression chains or improper handling of compressed data, potentially causing denial-of-service conditions. There are no known exploits in the wild at this time. The issues affect Red Hat Enterprise Linux 9.4 Extended Update Support and related variants using python3.12-urllib3.
Mitigation Recommendations
Red Hat has released updated python3.12-urllib3 packages that address these vulnerabilities. Users of affected Red Hat Enterprise Linux 9.4 Extended Update Support systems should apply the provided security updates as detailed in the Red Hat advisory RHSA-2026:1957 and the referenced article https://access.redhat.com/articles/11258. Applying these updates will remediate the vulnerabilities. No additional mitigation actions 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-2026:1957
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-66471","CVE-2026-21441"]
- Cvss Version
- null
Threat ID: 6a16096be29bf47b50631958
Added to database: 5/26/2026, 8:58:19 PM
Last enriched: 5/27/2026, 1:21:06 AM
Last updated: 5/27/2026, 4:49:19 AM
Views: 2
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