Red Hat Security Advisory: osbuild-composer security update

Fixed packages 9

Vulnerabilities 6

• Critical 9.1
  CVE-2025-68121

  Unexpected session resumption in crypto/tls

  During session resumption in crypto/tls, if the underlying Config has its ClientCAs or RootCAs fields mutated between the initial handshake and the resumed handshake, the resumed handshake may succeed when it should have failed. This may happen when a user ca…

  Go standard library crypto/tls langfuse-3-worker katib-suggestion-hyperopt Debian Ubuntu Azure Linux Alpine Wolfi Go
  Feb 5, 2026
• High 7.5
  CVE-2026-25679

  Incorrect parsing of IPv6 host literals in net/url

  url.Parse insufficiently validated the host/authority component and accepted some invalid URLs.

  Go standard library net/url langfuse-3-worker katib-suggestion-hyperopt Debian Ubuntu Azure Linux Alpine Wolfi Go
  Mar 6, 2026
• High 7.5
  CVE-2026-32280

  Unexpected work during chain building in crypto/x509

  During chain building, the amount of work that is done is not correctly limited when a large number of intermediate certificates are passed in VerifyOptions.Intermediates, which can lead to a denial of service. This affects both direct users of crypto/x509 an…

  Go standard library crypto/x509 golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Apr 8, 2026
• High 7.5
  CVE-2026-32281

  Inefficient policy validation in crypto/x509

  Validating certificate chains which use policies is unexpectedly inefficient when certificates in the chain contain a very large number of policy mappings, possibly causing denial of service. This only affects validation of otherwise trusted certificate chain…

  Go standard library crypto/x509 golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Apr 8, 2026
• High 7.5
  CVE-2026-32283

  Unauthenticated TLS 1.3 KeyUpdate record can cause persistent connection retention and DoS in crypto/tls

  If one side of the TLS connection sends multiple key update messages post-handshake in a single record, the connection can deadlock, causing uncontrolled consumption of resources. This can lead to a denial of service. This only affects TLS 1.3.

  Go standard library crypto/tls golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Apr 8, 2026
• Medium 6.4
  CVE-2026-32282

  TOCTOU permits root escape on Linux via Root.Chmod in os in internal/syscall/unix

  On Linux, if the target of Root.Chmod is replaced with a symlink while the chmod operation is in progress, Chmod can operate on the target of the symlink, even when the target lies outside the root. The Linux fchmodat syscall silently ignores the AT_SYMLINK_N…

  Go standard library internal/syscall/unix golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  Apr 8, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2437111
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2445356
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2456333
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2456336
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2456338
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2456339
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_48036.json
• report
  https://access.redhat.com/security/cve/CVE-2025-68121
• advisory
  https://www.cve.org/CVERecord?id=CVE-2025-68121
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2025-68121
• article
  https://go.dev/cl/737700
• article
  https://go.dev/issue/77217
• article
  https://groups.google.com/g/golang-announce/c/K09ubi9FQFk
• advisory
  https://pkg.go.dev/vuln/GO-2026-4337
• report
  https://access.redhat.com/security/cve/CVE-2026-25679
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-25679
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-25679
• article
  https://go.dev/cl/752180
• article
  https://go.dev/issue/77578
• article
  https://groups.google.com/g/golang-announce/c/EdhZqrQ98hk
• advisory
  https://pkg.go.dev/vuln/GO-2026-4601
• report
  https://access.redhat.com/security/cve/CVE-2026-32280
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-32280
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-32280
• article
  https://go.dev/cl/758320
• article
  https://go.dev/issue/78282
• article
  https://groups.google.com/g/golang-announce/c/0uYbvbPZRWU
• advisory
  https://pkg.go.dev/vuln/GO-2026-4947
• report
  https://access.redhat.com/security/cve/CVE-2026-32281
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-32281
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-32281
• article
  https://go.dev/cl/758061
• article
  https://go.dev/issue/78281
• advisory
  https://pkg.go.dev/vuln/GO-2026-4946
• report
  https://access.redhat.com/security/cve/CVE-2026-32282
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-32282
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-32282
• article
  https://go.dev/cl/763761