Red Hat Security Advisory: OpenShift Container Platform 4.19.43 packages and security update

Fixed packages 17

Vulnerabilities 3

• High 7.5
  CVE-2026-33811

  Crash when handling long CNAME response in net

  When using LookupCNAME with the cgo DNS resolver, a very long CNAME response can trigger a double-free of C memory and a crash.

  Go standard library net golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  May 7, 2026
• High 7.5
  CVE-2026-39820

  Quadratic string concatentation in consumeComment in net/mail

  Well-crafted inputs reaching ParseAddress, ParseAddressList, and ParseDate were able to trigger excessive CPU exhaustion and memory allocations.

  Go standard library net/mail golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  May 7, 2026
• High 7.5
  CVE-2026-42499

  Quadratic string concatenation in consumePhrase in net/mail

  Pathological inputs could cause DoS through consumePhrase when parsing an email address according to RFC 5322.

  Go standard library net/mail golang go Debian Ubuntu Azure Linux Alpine Wolfi Go
  May 7, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#important
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2467809
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2467820
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2467822
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_54552.json
• report
  https://access.redhat.com/security/cve/CVE-2026-33811
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-33811
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-33811
• article
  https://go.dev/cl/767860
• article
  https://go.dev/issue/78803
• article
  https://groups.google.com/g/golang-announce/c/qcCIEXso47M
• advisory
  https://pkg.go.dev/vuln/GO-2026-4981
• report
  https://access.redhat.com/security/cve/CVE-2026-39820
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-39820
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-39820
• article
  https://go.dev/cl/759940
• article
  https://go.dev/issue/78566
• advisory
  https://pkg.go.dev/vuln/GO-2026-4986
• report
  https://access.redhat.com/security/cve/CVE-2026-42499
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-42499
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-42499
• article
  https://go.dev/cl/771520
• article
  https://go.dev/issue/78987
• advisory
  https://pkg.go.dev/vuln/GO-2026-4977