Amazon Linux 2 Security Advisory: ALAS2-2026-3796
Advisory Released Date: 2026-07-08
Advisory Updated Date: 2026-07-08
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. (CVE-2026-11774)
Affected Packages:
389-ds-base
Note:
This advisory is applicable to Amazon Linux 2 (AL2) Core repository. Visit this FAQ section for the difference between AL2 Core and AL2 Extras advisories.
Issue Correction:
Run yum update 389-ds-base or yum update --advisory ALAS2-2026-3796 to update your system.
aarch64:
389-ds-base-1.3.10.2-17.amzn2.0.7.aarch64
389-ds-base-libs-1.3.10.2-17.amzn2.0.7.aarch64
389-ds-base-devel-1.3.10.2-17.amzn2.0.7.aarch64
389-ds-base-snmp-1.3.10.2-17.amzn2.0.7.aarch64
389-ds-base-debuginfo-1.3.10.2-17.amzn2.0.7.aarch64
i686:
389-ds-base-1.3.10.2-17.amzn2.0.7.i686
389-ds-base-libs-1.3.10.2-17.amzn2.0.7.i686
389-ds-base-devel-1.3.10.2-17.amzn2.0.7.i686
389-ds-base-snmp-1.3.10.2-17.amzn2.0.7.i686
389-ds-base-debuginfo-1.3.10.2-17.amzn2.0.7.i686
src:
389-ds-base-1.3.10.2-17.amzn2.0.7.src
x86_64:
389-ds-base-1.3.10.2-17.amzn2.0.7.x86_64
389-ds-base-libs-1.3.10.2-17.amzn2.0.7.x86_64
389-ds-base-devel-1.3.10.2-17.amzn2.0.7.x86_64
389-ds-base-snmp-1.3.10.2-17.amzn2.0.7.x86_64
389-ds-base-debuginfo-1.3.10.2-17.amzn2.0.7.x86_64