Red Hat Security Advisory: osbuild-composer security update

Fixed packages 8

Vulnerabilities 7

• High 8.7
  CVE-2026-84445

  gRPC-Go: Denial of Service (DoS) via crash due to missing `:authority` and `Host` headers in the xDS servers

  gRPC-Go is the Go language implementation of gRPC. Prior to 1.82.2 and 1.83.2, servers created with xds.NewGRPCServer() allow internal/transport/http2_server.go to accept an RPC containing neither the :authority header nor the Host header, while RouteAndProce…

  grpc grpc-go katib-suggestion-hyperopt katib-suggestion-goptuna-compat Debian Ubuntu Azure Linux Wolfi Go
  Sep 14, 2026
• High 7.5
  CVE-2026-42504

  Quadratic complexity in WordDecoder.DecodeHeader in mime

  Decoding a maliciously-crafted MIME header containing many invalid encoded-words can consume excessive CPU.

  Go standard library mime golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Jun 2, 2026
• High 7.5
  CVE-2026-78667

  Lack of limit on size of parsed Range headers in net/http

  When parsing a Range header containing a large number of small ranges, FileServer(FS), ServeContent, and ServeFile(FS) can consume an excessive amount of CPU.

  Go standard library net/http golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Oct 8, 2026
• High 7.5
  CVE-2026-78669

  Excessive CPU consumption from repeated initial window changes in net/http

  A malicious HTTP/2 peer can cause excessive CPU consumption in the client or server by opening a large number of streams and then sending many small SETTINGS frames containing SETTINGS_INITIAL_WINDOW_SIZE values.

  Go standard library golang.org/x/net net/http golang.org/x/net/http2 Debian Ubuntu Azure Linux Alpine Wolfi Go
  Oct 8, 2026
• High 7.5
  CVE-2026-94440

  Memory limit bypass when parsing MIME headers in net/textproto, mime/multipart

  Parsing a multipart form can bypass memory limits and read an arbitrarily long line into memory when the remaining limit at the start of a part is less than 400 bytes.

  Go standard library net/textproto mime/multipart golang Debian Ubuntu Azure Linux Alpine Wolfi Go
  Oct 8, 2026
• High 7.5
  CVE-2026-97031

  Reject malformed ECH outer extension references in crypto/tls

  Multiple ECH outer extension references are not permitted under RFC 9849; previously, a client could send a well-crafted packet that could trigger memory exhaustion in the server process by specifying multiple references. We now reject these as malformed and …

  Go standard library crypto/tls golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Oct 8, 2026
• Medium 6.8
  CVE-2026-111943 Public exploit

  Distrust compromised intermediate certificates in crypto/x509

  On most platforms, Go uses the given system root certificates. However, in some narrower cases, the system trust stores may not be updated without further action. To defend against the narrower set of cases that may remain affected, a denylist was added in cr…

  Go standard library crypto/x509 golang go Debian Ubuntu Azure Linux Alpine Wolfi Go crates.io
  Oct 21, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2484204
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2533175
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2548334
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2548336
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2548341
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2548344
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2556068
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_91587.json
• report
  https://access.redhat.com/security/cve/CVE-2026-42504
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-42504
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-42504
• article
  https://go.dev/cl/774481
• article
  https://go.dev/issue/79217
• article
  https://groups.google.com/g/golang-announce/c/tKs3rmcBcKw
• advisory
  https://pkg.go.dev/vuln/GO-2026-5038
• report
  https://access.redhat.com/security/cve/CVE-2026-78667
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-78667
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-78667
• article
  https://go.dev/cl/847309
• article
  https://go.dev/issue/81858
• article
  https://groups.google.com/g/golang-announce/c/U2fTuyDJznI
• advisory
  https://pkg.go.dev/vuln/GO-2026-6609
• report
  https://access.redhat.com/security/cve/CVE-2026-78669
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-78669
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-78669
• article
  https://go.dev/cl/847186
• article
  https://go.dev/cl/847308
• article
  https://go.dev/issue/81742
• article
  https://groups.google.com/g/golang-announce/c/ZPwCyRUuGBs
• advisory
  https://pkg.go.dev/vuln/GO-2026-6611
• report
  https://access.redhat.com/security/cve/CVE-2026-84445
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-84445
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-84445
• article
  https://github.com/grpc/grpc-go/commit/3822494d8ea03b992c089fd2a195f041762fffb7
• article
  https://github.com/grpc/grpc-go/commit/8668b69c167df908b6b3666dcbf40992b9e932a4
• article
  https://github.com/grpc/grpc-go/commit/93e31b48545e2a8aaeb6e06b47fb249f94e6297f
• article
  https://github.com/grpc/grpc-go/issues/9354
• article
  https://github.com/grpc/grpc-go/pull/9365