Vulnerability Report

CVE-2026-12528

Title: 389 Directory Server Heap Buffer Overflow

Memory Corruption

Proof Of Concept

No public PoC currently indexed for CVE-2026-12528.

CWE Category CWE-787
Published Date Jun 17, 2026
Modified Date Jun 28, 2026
Exploit Status Not Found
Score 5.4 CVSS v3.1
Exploit Probability (EPSS)
0.23%

Vulnerability Summary

CVE-2026-12528: A flaw was found in 389 Directory Server in the __aclp__normalize_acltxt() function of aclparse.c. A malformed ACI (Access Control Instruction) string can trigger heap-buffer-overflow writes and reads during ACI parsing. The function fails to validate that the ACI keyword has sufficient length after whitespace stripping, leading to a 1-byte out-of-bounds write and subsequent out-of-bounds reads. An authenticated user with write access to the aci attribute could send a crafted ACI value to silently corrupt heap memory in the directory server process.

Impacted Vendors

R
redhat 1
F
fedora 1

Reference Links

https://access.redhat.com/security/cve/CVE-2026-12528 https://bugzilla.redhat.com/show_bug.cgi?id=2489835 https://github.com/389ds/389-ds-base/pull/7542
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
5.4
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L
CVSS v3.1
Source Entity [email protected]
Severity MEDIUM
5.4
Attack Vector
NETWORK
Complexity
LOW
Privileges
N/A
Interaction
NONE
Confidentiality
N/A
Integrity
N/A
Availability
N/A
Scope
UNCHANGED
RAW VECTOR CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

Associated Attack Patterns (CAPEC)

Total: Patterns

CVE-2026-12528 Exploits & PoCs (Proof Of Concept)

No public PoCs found in our database for this CVE.

MODIFIED

Vulnerability data updated via NVD.

MODIFIED

Vulnerability data updated via NVD.

Attack Vector Matrix

Access Vector NETWORK
Complexity LOW
Privileges N/A
Interaction NONE
CVSS Vector String CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

Affected Stack

No specific products linked.