Red Hat Security Advisory: fence-agents security update
The fence-agents packages provide a collection of scripts for handling remote power management for cluster devices. They allow failed or unreachable nodes to be forcibly restarted and removed from the cluster. Security Fix(es): * urllib3: urllib3: Unbounded decompression chain leads to resource exhaustion (CVE-2025-66418) * urllib3: urllib3 Streaming API improperly handles highly compressed data (CVE-2025-66471) * urllib3: urllib3 vulnerable to decompression-bomb safeguard bypass when following HTTP redirects (streaming API) (CVE-2026-21441) 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.
AI Analysis
Technical Summary
The fence-agents packages in Red Hat Enterprise Linux 8 provide scripts for remote power management of cluster devices, enabling forced restart and removal of failed or unreachable nodes. Security fixes address three vulnerabilities in the urllib3 library: CVE-2025-66418 (unbounded decompression chain causing resource exhaustion), CVE-2025-66471 (improper handling of highly compressed data in the streaming API), and CVE-2026-21441 (decompression-bomb safeguard bypass during HTTP redirects in the streaming API). These vulnerabilities could potentially be exploited to cause resource exhaustion or bypass safeguards related to decompression of data streams. Red Hat has issued an important security advisory (RHSA-2026:1240) with updates for affected packages.
Potential Impact
The vulnerabilities could lead to resource exhaustion on systems using the affected fence-agents packages due to unbounded decompression chains or improper handling of compressed data. This may affect cluster stability by impacting the remote power management scripts. There are no known exploits in the wild at this time. The severity is rated as important by Red Hat, indicating a significant but not critical impact.
Mitigation Recommendations
Red Hat has released updated fence-agents packages that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:1240 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor advisory.
Red Hat Security Advisory: fence-agents security update
Description
The fence-agents packages provide a collection of scripts for handling remote power management for cluster devices. They allow failed or unreachable nodes to be forcibly restarted and removed from the cluster. Security Fix(es): * urllib3: urllib3: Unbounded decompression chain leads to resource exhaustion (CVE-2025-66418) * urllib3: urllib3 Streaming API improperly handles highly compressed data (CVE-2025-66471) * urllib3: urllib3 vulnerable to decompression-bomb safeguard bypass when following HTTP redirects (streaming API) (CVE-2026-21441) 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.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The fence-agents packages in Red Hat Enterprise Linux 8 provide scripts for remote power management of cluster devices, enabling forced restart and removal of failed or unreachable nodes. Security fixes address three vulnerabilities in the urllib3 library: CVE-2025-66418 (unbounded decompression chain causing resource exhaustion), CVE-2025-66471 (improper handling of highly compressed data in the streaming API), and CVE-2026-21441 (decompression-bomb safeguard bypass during HTTP redirects in the streaming API). These vulnerabilities could potentially be exploited to cause resource exhaustion or bypass safeguards related to decompression of data streams. Red Hat has issued an important security advisory (RHSA-2026:1240) with updates for affected packages.
Potential Impact
The vulnerabilities could lead to resource exhaustion on systems using the affected fence-agents packages due to unbounded decompression chains or improper handling of compressed data. This may affect cluster stability by impacting the remote power management scripts. There are no known exploits in the wild at this time. The severity is rated as important by Red Hat, indicating a significant but not critical impact.
Mitigation Recommendations
Red Hat has released updated fence-agents packages that address these vulnerabilities. Users should apply the security update as described in Red Hat advisory RHSA-2026:1240 and the referenced article https://access.redhat.com/articles/11258. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:1240
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-66471","CVE-2026-21441"]
Threat ID: 6a160973e29bf47b5063c72c
Added to database: 05/26/2026, 20:58:27 UTC
Last enriched: 08/10/2026, 17:57:37 UTC
Last updated: 09/10/2026, 22:04:10 UTC
Views: 98
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