CVE-2026-11774: 389-ds-base: 389-ds-base: integer overflow in sasl packet length bypasses size limit leading to heap buffer overflow

Severity: high (CVSS 7.6 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-11 · updated 2026-07-15
Weakness: CWE-190

Description

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.

Affected products

Red Hat Directory Server 11.5 E4S for RHEL 8: all versions — fixed in 8060020260702180044.0ca98e7e
Red Hat Directory Server 11.7 E4S for RHEL 8: all versions — fixed in 8080020260702180836.f969626e
Red Hat Directory Server 11.9 for RHEL 8: all versions — fixed in 8100020260702145313.37ed7c03
Red Hat Directory Server 12: all versions
Red Hat Directory Server 12.2 E4S for RHEL 9: all versions — fixed in 9020020260703060155.1674d574
Red Hat Directory Server 12.4 E4S for RHEL 9: all versions — fixed in 9040020260703055735.1674d574
Red Hat Directory Server 13.2: all versions — fixed in 1783452100
Red Hat Enterprise Linux 10: all versions — fixed in 0:3.2.0-8.el10_2
Red Hat Enterprise Linux 10.0 Extended Update Support: all versions — fixed in 0:3.0.6-19.el10_0
Red Hat Enterprise Linux 7 Extended Lifecycle Support: all versions — fixed in 0:1.3.11.1-13.el7_9
Red Hat Enterprise Linux 8: all versions — fixed in 8100020260626120929.25e700aa
Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support: all versions — fixed in 8040020260629123121.96015a92
Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On: all versions — fixed in 8040020260629123121.96015a92
Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support: all versions — fixed in 8060020260626130540.824efc52
Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On: all versions — fixed in 8060020260626130540.824efc52
Red Hat Enterprise Linux 8.8 Telecommunications Update Service: all versions — fixed in 8080020260630025241.6dbb3803
Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions: all versions — fixed in 8080020260630025241.6dbb3803
Red Hat Enterprise Linux 9: all versions — fixed in 0:2.8.0-8.el9_8
Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions: all versions — fixed in 0:2.2.4-19.el9_2
Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions: all versions — fixed in 0:2.4.5-26.el9_4
Red Hat Enterprise Linux 9.6 Extended Update Support: all versions — fixed in 0:2.6.1-22.el9_6

How to fix

Upgrade to a fixed version: Red Hat Directory Server 11.5 E4S for RHEL 8 8060020260702180044.0ca98e7e; Red Hat Directory Server 11.7 E4S for RHEL 8 8080020260702180836.f969626e; Red Hat Directory Server 11.9 for RHEL 8 8100020260702145313.37ed7c03; Red Hat Directory Server 12.2 E4S for RHEL 9 9020020260703060155.1674d574; Red Hat Directory Server 12.4 E4S for RHEL 9 9040020260703055735.1674d574; Red Hat Directory Server 13.2 1783452100; Red Hat Enterprise Linux 10 0:3.2.0-8.el10_2; Red Hat Enterprise Linux 10.0 Extended Update Support 0:3.0.6-19.el10_0; Red Hat Enterprise Linux 7 Extended Lifecycle Support 0:1.3.11.1-13.el7_9; Red Hat Enterprise Linux 8 8100020260626120929.25e700aa; Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support 8040020260629123121.96015a92; Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On 8040020260629123121.96015a92. Check the vendor advisory for mitigations.

References

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