Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:L
Primary rating from NVD.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Lifecycle Timeline
3DescriptionNVD
A flaw was found in 389 Directory Server. The ldap_utf8prev() function reads bytes before the start of a buffer without bounds checking, causing a heap buffer over-read in string filter parsing that may influence internal filter processing behavior.
AnalysisAI
Heap buffer over-read in Red Hat Directory Server's ldap_utf8prev() function exposes LDAP deployments to potential confidentiality, integrity, and availability impact via crafted string filter input. The flaw affects authenticated, network-accessible LDAP servers running Red Hat Directory Server 11, 12, and 13 as well as the 389-ds component shipped across Red Hat Enterprise Linux 6 through 10. No public exploit identified at time of analysis and the vulnerability is not listed in CISA KEV; however, its presence in filter parsing logic - a core LDAP code path - warrants prompt patching in internet-exposed or multi-tenant directory environments.
Technical ContextAI
389 Directory Server is Red Hat's enterprise LDAP implementation, distributed both as a standalone product (Red Hat Directory Server 11/12/13) and embedded in RHEL 6-10 (cpe:2.3:a:red_hat:red_hat_enterprise_linux_*). The vulnerable function ldap_utf8prev() is responsible for backward traversal of UTF-8 encoded byte sequences - a common operation when parsing LDAP search filter strings that may contain multi-byte characters. CWE-126 (Buffer Over-Read) describes the root cause: the function reads bytes at a memory address before the logical start of the allocated heap buffer without performing bounds validation. This over-read does not write data (distinguishing it from a buffer overflow), but it does expose arbitrary heap memory contents to the parsing logic, potentially influencing filter evaluation outcomes or leaking heap layout. The flaw resides specifically in the string filter parsing subsystem, meaning it is reachable via standard LDAP Search Request operations.
RemediationAI
The primary remediation is to apply the vendor-released patch from Red Hat once available; monitor https://access.redhat.com/security/cve/CVE-2026-11787 and the associated Bugzilla entry (https://bugzilla.redhat.com/show_bug.cgi?id=2485425) for patch release and exact fixed versions, which are not confirmed in currently available intelligence. No exact fix version can be cited at this time - absence of version data should not be interpreted as patch unavailability, only as unconfirmed status. As a compensating control until patching, restrict LDAP bind access to trusted, known-good clients by enforcing IP allowlists or firewall rules at the LDAP port (typically TCP 389/636), reducing the pool of principals who can supply crafted filter strings; this directly addresses the PR:L and AV:N prerequisites. Additionally, consider enabling LDAP access logging at the verbose level to detect anomalous filter strings containing unusual UTF-8 byte sequences, which may indicate exploitation attempts. Disabling anonymous binds (if not already done) has no direct impact since PR:L already requires credentials, but reduces overall attack surface. For RHEL deployments, subscribe to Red Hat errata notifications for the 389-ds package.
More in Red Hat Directory Server 11
View allDenial of service in Red Hat / 389 Directory Server (389-ds-base, versions since ~1.3.2/2013) allows an authenticated LD
Heap buffer overflow in 389 Directory Server (389-ds-base) SASL I/O layer allows authenticated remote attackers to crash
Information disclosure in 389 Directory Server (upstream of Red Hat Directory Server 11-13, shipped across RHEL 6-10) le
Remote denial of service in 389 Directory Server (Red Hat Directory Server 11/12/13 and Red Hat Enterprise Linux 6 throu
Remote unauthenticated denial of service in 389 Directory Server (389-ds-base, shipped as Red Hat Directory Server 11-13
Denial-of-service in Red Hat's 389 Directory Server allows a highly privileged network attacker to crash the LDAP servic
Heap buffer overflow in Red Hat 389 Directory Server allows an authenticated Directory Manager or a compromised replicat
Denial of service in Red Hat 389 Directory Server's Content Synchronization persistent search plugin enables authenticat
Out-of-bounds read in 389 Directory Server's LDIF parser exposes limited heap memory to a highly privileged local attack
Heap buffer overflow in 389 Directory Server's ACI parsing layer allows an authenticated LDAP user with write access to
Heap-buffer-overflow in 389 Directory Server's DN normalization routine allows an unauthenticated remote attacker to cor
Heap buffer overflow in Red Hat Directory Server (389-ds-base) exposes LDAP services to remote unauthenticated denial of
Same weakness CWE-126 – Buffer Over-read
View allSame technique Buffer Overflow
View allVendor StatusVendor
SUSE
Severity: Moderate| Product | Status |
|---|---|
| SUSE Linux Enterprise High Performance Computing 15 SP7 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server 15 SP7 | Affected |
| SUSE Linux Enterprise Server 16.0 | Affected |
| SUSE Linux Enterprise Server 16.1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP7 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.0 | Affected |
| SUSE Linux Enterprise Server for SAP applications 16.1 | Affected |
| openSUSE Leap 16.0 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP5 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP4-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP5 | Affected |
| SUSE Linux Enterprise Server 15 SP5-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP6 | Affected |
| SUSE Linux Enterprise Server 15 SP6-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP6 | Affected |
| SUSE Manager Proxy 4.3 | Affected |
| SUSE Manager Proxy LTS 4.3 | Affected |
| SUSE Manager Retail Branch Server 4.3 | Affected |
| SUSE Manager Retail Branch Server LTS 4.3 | Affected |
| SUSE Manager Server 4.3 | Affected |
| SUSE Manager Server LTS 4.3 | Affected |
| SUSE CaaS Platform 4.0 | Affected |
| SUSE Enterprise Storage 6 | Affected |
| SUSE Enterprise Storage 7 | Affected |
| SUSE Enterprise Storage 7.1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3 | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP4-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP5-ESPOS | Affected |
| SUSE Linux Enterprise High Performance Computing 15 SP6 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Module for Server Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP2 | Affected |
| SUSE Linux Enterprise Real Time 15 SP3 | Affected |
| SUSE Linux Enterprise Real Time 15 SP4 | Affected |
| SUSE Linux Enterprise Server 15 SP1 | Affected |
| SUSE Linux Enterprise Server 15 SP1-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP1-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP2 | Affected |
| SUSE Linux Enterprise Server 15 SP2-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP2-LTSS | Affected |
| SUSE Linux Enterprise Server 15 SP3 | Affected |
| SUSE Linux Enterprise Server 15 SP3-BCL | Affected |
| SUSE Linux Enterprise Server 15 SP3-LTSS | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP1 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP2 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP3 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP4 | Affected |
| SUSE Linux Enterprise Server for SAP Applications 15 SP5 | Affected |
| SUSE Manager Proxy 4.0 | Affected |
| SUSE Manager Proxy 4.1 | Affected |
| SUSE Manager Proxy 4.2 | Affected |
| SUSE Manager Retail Branch Server 4.0 | Affected |
| SUSE Manager Retail Branch Server 4.1 | Affected |
| SUSE Manager Retail Branch Server 4.2 | Affected |
| SUSE Manager Server 4.0 | Affected |
| SUSE Manager Server 4.1 | Affected |
| SUSE Manager Server 4.2 | Affected |
| openSUSE Leap 15.3 | Affected |
| openSUSE Leap 15.4 | Affected |
| openSUSE Leap 15.5 | Affected |
| openSUSE Leap 15.6 | Affected |
| suse/389-ds | Affected |
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External POC / Exploit Code
Leaving vuln.today
EUVD-2026-35419
GHSA-wjcg-9hh3-8323