Red Hat Security Advisory: 389-ds-base security, bug fix, and enhancement update

Fixed packages 7

Vulnerabilities 4

• Critical 9.8
  CVE-2026-18922

  389-ds-base: 389-ds-base: sasl plain authentication allows privilege escalation to directory manager via stale identity in cyrus sasl auxiliary property

  A flaw was found in 389 Directory Server. During SASL PLAIN authentication, a stale identity carried in a Cyrus SASL auxiliary property from a prior failed bind attempt can be installed on a connection following a subsequent, unrelated successful bind, regard…

  Red Hat Red Hat Enterprise Linux 9 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 10 Linux Debian Ubuntu Azure Linux
  Sep 7, 2026
• High 7.5
  CVE-2026-18355

  389-ds-base: 389-ds-base: heap buffer overflow via sasl wrapped-record length lower-bound underflow in sasl_io_start_packet()

  A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), the wrapped-record length read from the wire is validated only against an upper bound. A small wire length (0, 1, or 2) produces an e…

  Red Hat Red Hat Enterprise Linux 9 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 6 Linux Debian Ubuntu Azure Linux
  Sep 7, 2026
• High 7.5
  CVE-2026-18453

  389-ds-base: 389-ds-base: pre-authentication null pointer dereference via paged results and use_one_backend control in op_shared_search

  A flaw was found in 389 Directory Server. A missing NULL pointer check in the paged results handling of op_shared_search allows an unauthenticated remote attacker to crash the LDAP server by sending a crafted sequence of search requests using the USE_ONE_BACK…

  Red Hat Red Hat Enterprise Linux 9 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 6 Linux Debian Ubuntu Azure Linux
  Sep 7, 2026
• High 7.5
  CVE-2026-76560

  389-ds-base: 389-ds: anonymous ldap client can defeat selfdn aci bind-rule checks via empty bind dn

  A flaw was found in 389 Directory Server. The SELFDN ACI bind-rule evaluator incorrectly matches an anonymous LDAP client's empty bind DN against an empty stored attribute value, allowing an unauthenticated client to satisfy access control checks intended to …

  Red Hat Red Hat Enterprise Linux 9 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 6 Linux Debian Ubuntu Azure Linux
  Sep 7, 2026

References

• article
  https://access.redhat.com/security/updates/classification/#critical
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2509186
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2509696
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2511388
• report
  https://bugzilla.redhat.com/show_bug.cgi?id=2519521
• advisory
  https://security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_64781.json
• report
  https://access.redhat.com/security/cve/CVE-2026-18355
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-18355
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-18355
• report
  https://access.redhat.com/security/cve/CVE-2026-18453
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-18453
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-18453
• report
  https://access.redhat.com/security/cve/CVE-2026-18922
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-18922
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-18922
• report
  https://access.redhat.com/security/cve/CVE-2026-76560
• advisory
  https://www.cve.org/CVERecord?id=CVE-2026-76560
• advisory
  https://nvd.nist.gov/vuln/detail/CVE-2026-76560