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389 Directory Server EUVDEUVD-2026-36293

| CVE-2026-11774 HIGH
Integer Overflow or Wraparound (CWE-190)
2026-06-11 redhat GHSA-6mrg-rm5v-2c3q
Integer Overflow RCE Denial Of Service Red Hat Buffer Overflow Red Hat Directory Server 11 Red Hat Directory Server 12 Red Hat Directory Server 13 Red Hat Enterprise Linux 10 Red Hat Enterprise Linux 6 Red Hat Enterprise Linux 7 Red Hat Enterprise Linux 8 Red Hat Enterprise Linux 9
7.6
CVSS 3.1 · Vendor: redhat
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Severity by source

Vendor (redhat) PRIMARY
7.6 HIGH
AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
vuln.today AI
7.6 HIGH

Network-reachable LDAP (AV:N), deterministic overflow trigger (AC:L), requires a successful SASL bind so PR:L; RCE potential gives some C/I impact but reliable outcome is service crash, hence A:H with C:L/I:L.

3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
4.0 AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:H/SC:N/SI:N/SA:N
SUSE
HIGH
qualitative
Red Hat
7.6 HIGH
qualitative

Primary rating from Vendor (redhat).

CVSS VectorVendor: redhat

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H
Attack Vector
Network
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
Low
Availability
High

Lifecycle Timeline

2
Analysis Generated
Jun 11, 2026 - 19:15 vuln.today
CVE Published
Jun 11, 2026 - 17:54 cve.org
HIGH 7.6

DescriptionCVE.org

An integer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), 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. After a successful SASL bind with integrity protection (SSF > 0), a remote attacker can cause a Denial of Service (DoS) or achieve Remote Code Execution (RCE). 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. This flaw is independent of CVE-2025-14905, which patched schema.c only and did not modify sasl_io.c.

AnalysisAI

Heap buffer overflow in 389 Directory Server (389-ds-base) SASL I/O layer allows authenticated remote attackers to crash the LDAP service or achieve remote code execution after a successful SASL bind with integrity protection (SSF > 0). The flaw stems from an integer overflow in sasl_io_start_packet() that bypasses the nsslapd-maxsasliosize ceiling, enabling roughly 2 MB of attacker-controlled heap corruption. No public exploit identified at time of analysis, and the impact is amplified in FreeIPA and Red Hat Identity Management deployments where any enrolled user, host, or service principal qualifies as an authenticated attacker.

Technical ContextAI

389 Directory Server is the upstream LDAP implementation behind Red Hat Directory Server and the identity backbone of FreeIPA / Red Hat Identity Management. The bug lives in the SASL framing code (sasl_io.c, function sasl_io_start_packet) that reads the 4-byte length prefix preceding each SASL-wrapped LDAP message. The implementation adds sizeof(uint32_t) (4) to the attacker-supplied length to allocate a receive buffer; a crafted prefix of 0xFFFFFFFC wraps the unsigned 32-bit addition to 0, defeating the nsslapd-maxsasliosize sanity check and causing a vastly undersized allocation that is then filled with up to ~2 MB of attacker bytes - a textbook CWE-190 integer overflow leading to a heap buffer overflow. The advisory explicitly notes this is a distinct code path from CVE-2025-14905, which only repaired schema.c and left sasl_io.c untouched. CPE data covers Red Hat Directory Server 11/12/13 and the 389-ds-base packages shipped in RHEL 6 through 10.

RemediationAI

No vendor-released patch identified at time of analysis from the supplied references; monitor https://access.redhat.com/security/cve/CVE-2026-11774 and the linked Bugzilla 2484916 for fixed package versions (389-ds-base for RHEL 8/9/10 and redhat-ds for RHDS 11/12/13) and apply them as soon as they ship, prioritizing IdM/FreeIPA replicas. Until a patch is available, the most direct compensating control is to restrict SASL bind exposure - lower nsslapd-maxsasliosize toward the smallest value compatible with your largest legitimate SASL message (note this only narrows, not eliminates, the overflow window because the overflow bypasses the check entirely) and front the LDAP/LDAPS ports (389/636/3268/3269) with host firewall rules that allow only trusted client subnets and replication peers, accepting that IdM clients still need access. Where feasible, disable SASL mechanisms that negotiate integrity or confidentiality (SSF > 0) on edge replicas, but be aware this breaks GSSAPI/Kerberos binds and will disrupt FreeIPA enrollment, kinit-based logins, and replication, so it is realistic only for read-only consumer instances. Increase monitoring of ns-slapd for unexpected crashes or restarts and audit Kerberos principal issuance to limit the population of attackers who can complete a SASL bind.

More in Red Hat Directory Server 11

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Denial of service in Red Hat / 389 Directory Server (389-ds-base, versions since ~1.3.2/2013) allows an authenticated LD
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7.5 Jul 31

Information disclosure in 389 Directory Server (upstream of Red Hat Directory Server 11-13, shipped across RHEL 6-10) le
CVE-2026-11788 HIGH
7.5 Jun 09

Remote denial of service in 389 Directory Server (Red Hat Directory Server 11/12/13 and Red Hat Enterprise Linux 6 throu
CVE-2026-15722 HIGH
7.5 Jul 31

Remote unauthenticated denial of service in 389 Directory Server (389-ds-base, shipped as Red Hat Directory Server 11-13
CVE-2026-11789 MEDIUM
6.5 Jun 09

Denial-of-service in Red Hat's 389 Directory Server allows a highly privileged network attacker to crash the LDAP servic
CVE-2026-11884 MEDIUM
6.5 Jun 10

Heap buffer overflow in Red Hat 389 Directory Server allows an authenticated Directory Manager or a compromised replicat
CVE-2026-11611 MEDIUM
6.5 Jun 08

Denial of service in Red Hat 389 Directory Server's Content Synchronization persistent search plugin enables authenticat
CVE-2026-11786 MEDIUM
6.5 Jun 09

Out-of-bounds read in 389 Directory Server's LDIF parser exposes limited heap memory to a highly privileged local attack
CVE-2026-11787 MEDIUM
6.3 Jun 09

Heap buffer over-read in Red Hat Directory Server's ldap_utf8prev() function exposes LDAP deployments to potential confi
CVE-2026-12528 MEDIUM
5.4 Jun 17

Heap buffer overflow in 389 Directory Server's ACI parsing layer allows an authenticated LDAP user with write access to

CVE-2026-14940 MEDIUM
5.3 Jul 07

Heap-buffer-overflow in 389 Directory Server's DN normalization routine allows an unauthenticated remote attacker to cor
CVE-2026-16560 MEDIUM
5.3 Jul 22

Heap buffer overflow in Red Hat Directory Server (389-ds-base) exposes LDAP services to remote unauthenticated denial of

Same weakness CWE-190 – Integer Overflow or Wraparound

View all
CVE-2013-2729 CRITICAL POC
9.8
CVE-2015-8651 HIGH
8.8
CVE-2012-5054 HIGH POC
8.8
CVE-2014-0569 CRITICAL POC
9.3
CVE-2017-3599 HIGH POC
7.5
CVE-2017-7529 HIGH
7.5
CVE-2016-1010 HIGH
8.8
CVE-2013-3940 CRITICAL
9.3

Same technique Integer Overflow

View all
CVE-2014-0497 CRITICAL POC
9.8
CVE-2013-2729 CRITICAL POC
9.8
CVE-2015-8651 HIGH
8.8
CVE-2012-5054 HIGH POC
8.8
CVE-2014-0569 CRITICAL POC
9.3
CVE-2017-3599 HIGH POC
7.5
CVE-2017-7529 HIGH
7.5
CVE-2016-1010 HIGH
8.8

Vendor StatusVendor

SUSE

Severity: Important
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

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EUVD-2026-36293 vulnerability details – vuln.today
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