Bug 2494774

Summary: CVE-2026-11787 389-ds-base: 389-ds-base: heap buffer over-read in ldap_utf8prev() via str2simple filter parsing [fedora-all]
Product: [Fedora] Fedora Reporter: Samuele Negrini <snegrini>
Component: 389-ds-baseAssignee: mreynolds
Status: NEW --- QA Contact: Fedora Extras Quality Assurance <extras-qa>
Severity: medium Docs Contact:
Priority: medium    
Version: 45CC: abokovoy, jachapma, mreynolds, spichugi, tbordaz, vashirov
Target Milestone: ---Keywords: Security, SecurityTracking
Target Release: ---Flags: fedora-admin-xmlrpc: mirror+
Hardware: Unspecified   
OS: Unspecified   
Whiteboard: {"flaws": ["fc6b9bfd-ac74-4291-a73d-8bb2d56a47f6"]}
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On:    
Bug Blocks: 2485425    

Description Samuele Negrini 2026-06-30 07:31:00 UTC 
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.

The ldap_utf8prev() function in 389 Directory Server unconditionally reads up to 6 bytes before a heap allocation because it lacks a lower-bound parameter. This API design flaw has existed since the Mozilla LDAP C SDK import and was symptomatically patched twice without fixing the root cause. Twenty call sites remain vulnerable to 1-6 byte heap over-reads.

Cannot be triggered via standard LDAP wire protocol (BER filters parsed separately), but internal callers processing attacker-influenced data (plugin configuration, ACI definitions, replication) are affected. ASan confirmed on aarch64; no crash on production binaries.
Comment 1 Aoife Moloney 2026-08-17 15:06:33 UTC 
This bug appears to have been reported against 'rawhide' during the Fedora Linux 45 development cycle.
Changing version to 45.