RHSA-2026:99758: Important: 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): google.golang.org/grpc: gRPC-Go: Denial of Service via malformed RPC requests (CVE-2026-84445) net/http: golang: golang: Denial of Service via crafted HTTP Range headers (CVE-2026-78667) crypto/tls: golang: crypto/tls: Denial of Service via multiple ECH outer extension references (CVE-2026-97031) net/textproto: mime/multipart: golang: golang: Denial of Service via memory limit bypass in multipart form parsing (CVE-2026-94440) net/http: net/http/internal/http2: golang.org/x/net/http2: net/http: Denial of Service via excessive HTTP/2 SETTINGS frames (CVE-2026-78669) 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
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/osbuild-composerto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-coreto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-core-debuginfoto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-debuginfoto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-debugsourceto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-dnf-jsonto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-tests-debuginfoto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-workerto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6 - Upgrade
Upgrade
redhat/osbuild-composer-worker-debuginfoto a version that resolves this vulnerability.Fixed in 46.3-12.el8_6
Event History
Frequently Asked Questions
Which components are included in this update?
The update covers osbuild-composer and related packages including osbuild-composer-core, osbuild-composer-worker, osbuild-composer-dnf-json, test packages, and available debuginfo and debugsource packages.
What types of impact do the addressed issues have?
All listed fixes address denial-of-service conditions. The affected Go components include gRPC request handling, HTTP Range-header processing, TLS ECH extension handling, multipart form parsing, and HTTP/2 SETTINGS-frame handling.