Red Hat Security Advisory: osbuild-composer security update
A service for building customized OS artifacts, such as VM images and OSTree commits, that uses osbuild under the hood. Besides building images for local usage, it can also upload images directly to cloud. It is compatible with composer-cli and cockpit-composer clients. 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) 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 osbuild-composer service in Red Hat Enterprise Linux 8.6 is affected by two vulnerabilities originating from golang components. CVE-2025-61729 involves a denial of service caused by excessive resource consumption when processing crafted certificates in the crypto/x509 package. CVE-2025-61726 involves memory exhaustion during query parameter parsing in the net/url package. These issues can cause the osbuild-composer service to consume excessive system resources, potentially leading to denial of service conditions. Red Hat has released security updates for osbuild-composer packages in multiple RHEL 8.6 variants to address these vulnerabilities.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service through excessive resource consumption or memory exhaustion, impacting the availability of the osbuild-composer service. This could disrupt the building and uploading of customized OS artifacts such as VM images and OSTree commits. There is no indication of known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released security updates for osbuild-composer in Red Hat Enterprise Linux 8.6 variants to address these vulnerabilities. Users should apply the available updates as described in the Red Hat advisory RHSA-2026:5853 (https://access.redhat.com/articles/11258) to remediate the issues. No additional mitigation steps are specified or required beyond applying the official patches.
Red Hat Security Advisory: osbuild-composer security update
Description
A service for building customized OS artifacts, such as VM images and OSTree commits, that uses osbuild under the hood. Besides building images for local usage, it can also upload images directly to cloud. It is compatible with composer-cli and cockpit-composer clients. 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) 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 osbuild-composer service in Red Hat Enterprise Linux 8.6 is affected by two vulnerabilities originating from golang components. CVE-2025-61729 involves a denial of service caused by excessive resource consumption when processing crafted certificates in the crypto/x509 package. CVE-2025-61726 involves memory exhaustion during query parameter parsing in the net/url package. These issues can cause the osbuild-composer service to consume excessive system resources, potentially leading to denial of service conditions. Red Hat has released security updates for osbuild-composer packages in multiple RHEL 8.6 variants to address these vulnerabilities.
Potential Impact
Successful exploitation of these vulnerabilities can cause denial of service through excessive resource consumption or memory exhaustion, impacting the availability of the osbuild-composer service. This could disrupt the building and uploading of customized OS artifacts such as VM images and OSTree commits. There is no indication of known exploits in the wild at this time.
Mitigation Recommendations
Red Hat has released security updates for osbuild-composer in Red Hat Enterprise Linux 8.6 variants to address these vulnerabilities. Users should apply the available updates as described in the Red Hat advisory RHSA-2026:5853 (https://access.redhat.com/articles/11258) to remediate the issues. No additional mitigation steps are specified or required beyond applying the official patches.
Technical Details
- Gcve Source
- db.gcve.eu
- Csaf Category
- csaf_security_advisory
- Csaf Version
- 2.0
- Publisher
- Red Hat Product Security
- Advisory Id
- RHSA-2026:5853
- Cve Count
- 2
- Additional Cves
- ["CVE-2025-61729"]
- Cvss Version
- null
Threat ID: 6a160964e29bf47b50629c45
Added to database: 05/26/2026, 20:58:12 UTC
Last enriched: 07/30/2026, 07:46:54 UTC
Last updated: 07/31/2026, 21:28:46 UTC
Views: 49
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