Heap corruption via malformed ACI parsing
Published Jun 17, 2026 · Updated Jun 17, 2026
Heap buffer overflow in Red Hat Directory Server allows remote authenticated users to corrupt heap memory through a malformed ACI value. The __aclp__normalize_acltxt() function in aclparse.c strips whitespace but fails to verify the remaining ACI keyword length before writing a terminator and reading subsequent bytes. Exploitation requires write access to the aci attribute and can silently corrupt memory in the directory-server process.
Summary
What happened
Heap buffer overflow in Red Hat Directory Server allows remote authenticated users to corrupt heap memory through a malformed ACI value. The __aclp__normalize_acltxt() function in aclparse.c strips whitespace but fails to verify the remaining ACI keyword length before writing a terminator and reading subsequent bytes. Exploitation requires write access to the aci attribute and can silently corrupt memory in the directory-server process.
The record
- CVE
- CVE-2026-12528
- Published
- Jun 17, 2026
- Updated
- Jun 17, 2026
- Vendor
- 389 Directory Server
- Product
- Red Hat Directory Server
- Classifications
- CWE-787, T1190
- Attack vector
- network
- Privileges
- authenticated
Timeline
How it unfolded
- Jun 17, 2026CVE publishedPublication date reported by the CVE source.
- Jun 17, 2026Record updatedLatest update available in the CVE record.
Exploitability
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What conditions does exploitation require?
What is affected?
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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