RHSA-2026:3753 — Security Advisory
Red Hat Security Advisory: osbuild-composer security update
Severity
ImportantRed Hat Product Security
Products
Official CSAF product identity
Published · March 5, 2026
Updated · November 4, 2026
Topic
An update for osbuild-composer is now available for Red Hat Enterprise Linux 9.
Red Hat Product Security has rated this update as having a security impact of Important. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section.
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)
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golang: archive/zip: Excessive CPU consumption when building archive index in archive/zip (CVE-2025-61728)
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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.