CVE-2026-11610
HighCVSS 8.8Exploitation Probability (EPSS)
Low risk46th percentile - higher than 46% of all known CVEs
Summary
A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). An authenticated attacker can send a specially crafted oversized LDAP UNBIND packet that overflows a 512-byte heap receive buffer without bounds checking, causing a denial of service (server crash).
Risk Assessment
In FreeIPA and Red Hat Identity Management deployments, any domain user with a valid Kerberos ticket, enrolled host, or service account can trigger this vulnerability over the network after authenticating via GSSAPI, leading to a denial of service.
Recommendation
Immediately update the 389-ds-base package to a version containing the fix. Until the update is applied, restrict network access to the LDAP server to trusted hosts and users only.
Other vulnerabilities in 389-ds-base
See all- CVE-2017-7551Critical
389-ds-base versions before 1.3.5.19 and 1.3.6.7 are vulnerable to password brute-force attacks during account lockout due to different return codes returned on password attempts.
- CVE-2026-19843High
A flaw in 389-ds-base, in the Cockpit 389 Console's LDAP editor. An LDAP entry's DN is embedded into a shell command without proper escaping. A user with delegated privileges could craft a malicious DN with shell metacharacters, leading to command execution with root privileges when viewed by an administrator.
- CVE-2026-78701Medium
A flaw was found in 389-ds-base. A remote, authenticated attacker could exploit a vulnerability in the 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.
- CVE-2026-18663Medium
A double-free flaw was found in 389-ds-base in the get_ldapmessage_controls_ext() function. An unauthenticated remote attacker can trigger it with a single BIND request carrying a critical Session Tracking control, leading to heap corruption and potential denial of service.
- CVE-2026-16560Medium
A heap-buffer-overflow flaw was found in Directory Server (389-ds-base). When a DN contains a legacy-quoted value, the server won't close the heap allocation allowing another call to refer to the same memory pointer causing a denial of service or an arbitrary memory write operation.
- CVE-2026-14969Medium
A flaw was found in 389-ds-base where the LDBM backend attribute encryption uses a hardcoded static initialization vector for AES-CBC and 3DES-CBC operations, allowing an attacker with privileged filesystem access to detect plaintext equality across encrypted entries by comparing ciphertext blocks.
- CVE-2026-14940Medium
A heap-buffer-overflow vulnerability was found in 389 Directory Server (389-ds-base). When normalizing a Distinguished Name (DN) that contains a legacy-quoted value encoding a multivalued nested Relative Distinguished Name (RDN), the server can write past the end of a heap allocation while sorting RDN attribute-value pairs. An unauthenticated remote attacker can trigger this condition by sending an LDAP operation whose DN reaches the DN normalization routine, such as a search with a crafted base DN.
- CVE-2026-11774High
An integer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). Adding sizeof(uint32_t) to a crafted SASL packet length prefix of 0xFFFFFFFC causes unsigned wraparound to zero, bypassing the nsslapd-maxsasliosize limit and leading to a heap buffer overflow of up to approximately 2 megabytes of attacker-controlled data.
- CVE-2026-9064High
In 389-ds-base, the get_ldapmessage_controls_ext() function does not enforce an upper bound on the number of controls per LDAP message. A remote, unauthenticated attacker can send a crafted request with hundreds of thousands of minimal controls, causing excessive CPU consumption and heap allocation.
- CVE-2025-14905High
A heap buffer overflow vulnerability was found in the 389-ds-base server in the `schema_attr_enum_callback` function within `schema.c`. The flaw is due to incorrect buffer size calculation that sums alias string lengths without accounting for formatting characters, which can cause a heap overflow when processing many aliases.
Original NVD description (English source)
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.

