{"id":"AZL-99980","summary":"CVE-2026-18355 affecting package 389-ds-base 3.1.1-12","details":"A heap buffer overflow flaw was found in the SASL I/O layer of 389 Directory Server (389-ds-base). In sasl_io_start_packet(), the wrapped-record length read from the wire is validated only against an upper bound. A small wire length (0, 1, or 2) produces an encrypted_buffer_count below the already-consumed encrypted_buffer_offset, causing an unsigned subtraction underflow in sasl_io_read_packet(). PR_Recv is then requested to read approximately 4 GiB into a 1024-byte heap buffer, resulting in a heap buffer overflow with attacker-controlled content. After a successful SASL bind with integrity protection (SSF \u003e 0), a remote authenticated attacker can cause a denial of service or potentially achieve remote code execution. This flaw is distinct from CVE-2026-11774, whose fix only guards against upper-bound overflow.","modified":"2026-09-14T05:26:26Z","published":"2026-09-07T15:17:30Z","upstream":["CVE-2026-18355"],"references":[{"type":"WEB","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-18355"}],"affected":[{"package":{"name":"389-ds-base","ecosystem":"Azure Linux:3","purl":"pkg:rpm/azure-linux/389-ds-base"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"last_affected":"3.1.1-12"}]}],"database_specific":{"source":"https://github.com/microsoft/AzureLinuxVulnerabilityData/blob/main/osv/AZL-99980.json"}}],"schema_version":"1.9.0"}