CVE-2026-11774389-ds-base: 389-ds-base: integer overflow in sasl packet length bypasses size limit leading to heap buffer overflow

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.

Timeline

Scores

EPSS (exploitation in 30 days)

0.68% · top 47% of all CVEs (13 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.6.

Affected products

• Red Hat · Red Hat Directory Server 11.5 E4S for RHEL 8

  • unaffected 8060020260702180044.0ca98e7e – < *

• Red Hat · Red Hat Directory Server 11.7 E4S for RHEL 8

  • unaffected 8080020260702180836.f969626e – < *

• Red Hat · Red Hat Directory Server 11.9 for RHEL 8

  • unaffected 8100020260702145313.37ed7c03 – < *

• Red Hat · Red Hat Directory Server 12.2 E4S for RHEL 9

  • unaffected 9020020260703060155.1674d574 – < *

• Red Hat · Red Hat Directory Server 12.4 E4S for RHEL 9

  • unaffected 9040020260703055735.1674d574 – < *

• Red Hat · Red Hat Enterprise Linux 10

  • unaffected 0:3.2.0-8.el10_2 – < *

• Red Hat · Red Hat Enterprise Linux 10.0 Extended Update Support

  • unaffected 0:3.0.6-19.el10_0 – < *

• Red Hat · Red Hat Enterprise Linux 7 Extended Lifecycle Support

  • unaffected 0:1.3.11.1-13.el7_9 – < *

• Red Hat · Red Hat Enterprise Linux 8

  • unaffected 8100020260626120929.25e700aa – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

  • unaffected 8040020260629123121.96015a92 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On

  • unaffected 8040020260629123121.96015a92 – < *

• Red Hat · Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support

  • unaffected 8060020260626130540.824efc52 – < *

• Red Hat · Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On

  • unaffected 8060020260626130540.824efc52 – < *

• Red Hat · Red Hat Enterprise Linux 8.8 Telecommunications Update Service

  • unaffected 8080020260630025241.6dbb3803 – < *

• Red Hat · Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions

  • unaffected 8080020260630025241.6dbb3803 – < *

• Red Hat · Red Hat Enterprise Linux 9

  • unaffected 0:2.8.0-8.el9_8 – < *

• Red Hat · Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions

  • unaffected 0:2.2.4-19.el9_2 – < *

• Red Hat · Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions

  • unaffected 0:2.4.5-26.el9_4 – < *

• Red Hat · Red Hat Enterprise Linux 9.6 Extended Update Support

  • unaffected 0:2.6.1-22.el9_6 – < *

• Red Hat · Red Hat Directory Server 13.2

  • unaffected 1783452100 – < *

• Red Hat · Red Hat Directory Server 12

  All versions: affected

• Red Hat · Red Hat Directory Server 13

  All versions: unaffected

• Red Hat · Red Hat Enterprise Linux 6

  All versions: unaffected

What to do

Workaround: No complete workaround exists; nsslapd-maxsasliosize is bypassed by the integer overflow. Mitigations that reduce exposure: restrict SASL mechanisms (disable DIGEST-MD5 if not required; GSSAPI cannot be disabled in FreeIPA/IdM without breaking Kerberos authentication); firewall LDAP ports (389/636) to trusted networks; monitor for SASL-framed packets with length prefix 0xFFFFFFFC through 0xFFFFFFFF; enable audit logging (nsslapd-auditlog-logging-enabled: on); on RHEL 8, upgrading glibc reduces RCE exploitability but does not eliminate DoS.

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• EUVD EUVD-2026-36293 (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2026-11774](https://cveledger.app/badge/CVE-2026-11774.svg)](https://cveledger.app/cve/CVE-2026-11774)

Record last updated 4 Nov 2026, 21:51 UTC.