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
The Red Hat image-builder tool, which builds customized OS artifacts using osbuild, is affected by three security vulnerabilities: CVE-2025-61729 (denial of service via crafted certificates in crypto/x509), CVE-2025-61726 (memory exhaustion during query parameter parsing in golang net/url), and CVE-2025-68121 (unexpected session resumption in crypto/tls). These vulnerabilities can cause excessive resource consumption or unexpected TLS session behavior. Red Hat has released an update for image-builder in Red Hat Enterprise Linux 10 to address these issues. The advisory includes updated packages for various architectures and references detailed remediation instructions. No CVSS scores are provided in the advisory, but the impact is rated as Important by Red Hat Product Security.
Potential Impact
The vulnerabilities may allow an attacker to cause denial of service through excessive resource consumption or trigger unexpected TLS session resumption behavior, potentially affecting the stability and security of systems using image-builder. The issues impact local processing of crafted certificates and URL query parameters, which could lead to memory exhaustion or denial of service conditions. There is no indication of known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released an official security update for image-builder in Red Hat Enterprise Linux 10 that addresses these vulnerabilities. Users should apply the update as described in the Red Hat advisory RHSA-2026:3840 and the referenced article https://access.redhat.com/articles/11258. This update includes fixes for CVE-2025-61729, CVE-2025-61726, and CVE-2025-68121. No additional mitigation steps are indicated beyond applying the official patch.
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
The Red Hat image-builder tool, which builds customized OS artifacts using osbuild, is affected by three security vulnerabilities: CVE-2025-61729 (denial of service via crafted certificates in crypto/x509), CVE-2025-61726 (memory exhaustion during query parameter parsing in golang net/url), and CVE-2025-68121 (unexpected session resumption in crypto/tls). These vulnerabilities can cause excessive resource consumption or unexpected TLS session behavior. Red Hat has released an update for image-builder in Red Hat Enterprise Linux 10 to address these issues. The advisory includes updated packages for various architectures and references detailed remediation instructions. No CVSS scores are provided in the advisory, but the impact is rated as Important by Red Hat Product Security.
Potential Impact
The vulnerabilities may allow an attacker to cause denial of service through excessive resource consumption or trigger unexpected TLS session resumption behavior, potentially affecting the stability and security of systems using image-builder. The issues impact local processing of crafted certificates and URL query parameters, which could lead to memory exhaustion or denial of service conditions. There is no indication of known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released an official security update for image-builder in Red Hat Enterprise Linux 10 that addresses these vulnerabilities. Users should apply the update as described in the Red Hat advisory RHSA-2026:3840 and the referenced article https://access.redhat.com/articles/11258. This update includes fixes for CVE-2025-61729, CVE-2025-61726, and CVE-2025-68121. No additional mitigation steps are indicated beyond applying the official patch.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:3840
- Cve Count
- 3
- Additional Cves
- ["CVE-2025-61729","CVE-2025-68121"]
- Cvss Version
- null
Threat ID: 6a160968e29bf47b5062e398
Added to database: 05/26/2026, 20:58:16 UTC
Last enriched: 07/30/2026, 08:01:28 UTC
Last updated: 07/31/2026, 21:28:46 UTC
Views: 52
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