Red Hat Security Advisory: image-builder security update
A local binary for building customized OS artifacts such as VM images and OSTree commits. Uses osbuild under the hood. Security Fix(es): * crypto/x509: golang: Denial of Service due to excessive resource consumption via crafted certificate (CVE-2025-61729) * golang: net/url: Memory exhaustion in query parameter parsing in net/url (CVE-2025-61726) * crypto/tls: Unexpected session resumption in crypto/tls (CVE-2025-68121) 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
This advisory covers security fixes for the image-builder tool in Red Hat Enterprise Linux 9, which is a local binary for building customized OS artifacts. The fixes address three vulnerabilities: CVE-2025-61729 (denial of service via excessive resource consumption from crafted certificates in crypto/x509), CVE-2025-61726 (memory exhaustion during query parameter parsing in net/url), and CVE-2025-68121 (unexpected session resumption in crypto/tls). These vulnerabilities could lead to denial of service or unexpected behavior in TLS session handling. The advisory provides updated packages for multiple architectures and variants of Red Hat Enterprise Linux 9. The vendor rates the update as Important and provides instructions for applying the update.
Potential Impact
The vulnerabilities can cause denial of service conditions due to excessive resource consumption or memory exhaustion, and may result in unexpected TLS session resumption behavior. These issues affect the image-builder tool's underlying golang libraries, potentially impacting the stability and security of systems using this tool to build OS artifacts. No known exploits in the wild have been reported. The impact is primarily local denial of service and potential TLS session handling anomalies.
Mitigation Recommendations
Red Hat has released updated image-builder packages that address these vulnerabilities. Users should apply the official security update for Red Hat Enterprise Linux 9 as described in the Red Hat advisory RHSA-2026:3839 (https://access.redhat.com/errata/RHSA-2026:3839). Applying this update will remediate the issues. No additional mitigations are indicated by the vendor advisory.
Red Hat Security Advisory: image-builder security update
Description
A local binary for building customized OS artifacts such as VM images and OSTree commits. Uses osbuild under the hood. Security Fix(es): * crypto/x509: golang: Denial of Service due to excessive resource consumption via crafted certificate (CVE-2025-61729) * golang: net/url: Memory exhaustion in query parameter parsing in net/url (CVE-2025-61726) * crypto/tls: Unexpected session resumption in crypto/tls (CVE-2025-68121) 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
This advisory covers security fixes for the image-builder tool in Red Hat Enterprise Linux 9, which is a local binary for building customized OS artifacts. The fixes address three vulnerabilities: CVE-2025-61729 (denial of service via excessive resource consumption from crafted certificates in crypto/x509), CVE-2025-61726 (memory exhaustion during query parameter parsing in net/url), and CVE-2025-68121 (unexpected session resumption in crypto/tls). These vulnerabilities could lead to denial of service or unexpected behavior in TLS session handling. The advisory provides updated packages for multiple architectures and variants of Red Hat Enterprise Linux 9. The vendor rates the update as Important and provides instructions for applying the update.
Potential Impact
The vulnerabilities can cause denial of service conditions due to excessive resource consumption or memory exhaustion, and may result in unexpected TLS session resumption behavior. These issues affect the image-builder tool's underlying golang libraries, potentially impacting the stability and security of systems using this tool to build OS artifacts. No known exploits in the wild have been reported. The impact is primarily local denial of service and potential TLS session handling anomalies.
Mitigation Recommendations
Red Hat has released updated image-builder packages that address these vulnerabilities. Users should apply the official security update for Red Hat Enterprise Linux 9 as described in the Red Hat advisory RHSA-2026:3839 (https://access.redhat.com/errata/RHSA-2026:3839). Applying this update will remediate the issues. No additional mitigations 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-2026:3839
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-61729","CVE-2025-68121"]
- Cvss Version
- null
Threat ID: 6a160968e29bf47b5062e424
Added to database: 05/26/2026, 20:58:16 UTC
Last enriched: 07/30/2026, 08:01:45 UTC
Last updated: 07/31/2026, 19:30:12 UTC
Views: 64
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