389-ds-base-2.8.0-10.el9_8

389 Directory Server is an LDAP version 3 (LDAPv3) compliant server. The base packages include the Lightweight Directory Access Protocol (LDAP) server and command-line utilities for server administration.

Security Fix(es):

* 389-ds-base: 389-ds-base: heap buffer overflow via SASL wrapped-record length lower-bound underflow in sasl_io_start_packet() (CVE-2026-18355)
* 389-ds-base: 389-ds-base: pre-authentication NULL pointer dereference via paged results and USE_ONE_BACKEND control in op_shared_search (CVE-2026-18453)
* 389-ds-base: 389-ds-base: SASL PLAIN authentication allows privilege escalation to Directory Manager via stale identity in Cyrus SASL auxiliary property (CVE-2026-18922)
* 389-ds-base: 389-ds: anonymous LDAP client can defeat SELFDN ACI bind-rule checks via empty bind DN (CVE-2026-76560)
* 389-ds-base: 389-ds-base: CVE-2026-11610 incomplete fix may introduce a connection-stall DoS (CVE-2026-78701)

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.

CVE-2026-11610
A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). After a successful SASL bind with integrity protection (SSF > 0), an authenticated attacker can send a specially crafted oversized LDAP UNBIND packet that is copied into a 512-byte heap receive buffer without a bounds check in sasl_io_recv() in sasl_io.c. This allows up to approximately 2 megabytes of attacker-controlled data to overflow the buffer, causing a denial of service (server crash). In FreeIPA and Red Hat Identity Management deployments, any domain user with a valid Kerberos ticket, any enrolled host, or any service account can trigger this vulnerability over the network after authenticating via GSSAPI. The vulnerable code path has existed since approximately 2013 (389-ds-base 1.3.2) and was not addressed by the CVE-2025-14905 fix, which patched a separate heap overflow in schema.c only.
CVE-2026-18355
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 encrypted_buffer_count below the already-consumed encrypted_buffer_offset, causing an unsigned subtraction underflow in sasl_io_read_packet(). PR_Recv is then requested to read approximately 4 GiB into a 1024-byte heap buffer, resulting in a heap buffer overflow with attacker-controlled content. After a successful SASL bind with integrity protection (SSF > 0), a remote authenticated attacker can cause a denial of service or potentially achieve remote code execution. This flaw is distinct from CVE-2026-11774, whose fix only guards against upper-bound overflow.
CVE-2026-18453
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_BACKEND control, resulting in denial of service.
CVE-2026-18922
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, regardless of which SASL mechanism completes that second bind. An attacker can send a SASL PLAIN bind as cn=Directory Manager with an incorrect password, then complete a SASL ANONYMOUS bind on the same connection, causing the server to grant Directory Manager authority without any valid credentials. A variant using a valid low-privileged account's own successful bind instead of an anonymous one is also possible.
CVE-2026-76560
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 require a matching authenticated identity. This can allow an anonymous LDAP client to perform an operation, such as adding or modifying a directory entry, that a SELFDN-based ACI intended to restrict to a specific authenticated user.
CVE-2026-78701
A flaw was found in 389-ds-base. A remote, authenticated attacker could exploit a vulnerability in the Simple Authentication and Security Layer (SASL) UNBIND process. By sending a specially crafted request, the attacker can cause a connection to stall, leading to resource exhaustion and a Denial of Service (DoS) for the server.