What is CVE-2026-12528?

CVE-2026-12528 is a medium-severity vulnerability in Red Hat Directory Server 11, classified under Out-of-bounds Write. CVSS score: 5.4/10. Published 2026-06-17.

How severe is CVE-2026-12528?

Medium severity. CVSS v3 base score is 5.4 out of 10.

Buffer overflow in Red Hat Directory Server 11

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…

Vulnerability class: Buffer Overflow

CVSS v3 metric

CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.

Affected products

Red Hat Directory Server 11
Red Hat Directory Server 12
Red Hat Directory Server 13
Red Hat Enterprise Linux 10
Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7
Red Hat Enterprise Linux 8
Red Hat Enterprise Linux 9

Weakness classification (CWE)

CWE-787 — Out-of-bounds Write

References

secalert@redhat.com (x_refsource_REDHAT, vdb-entry)
secalert@redhat.com (x_refsource_REDHAT, issue-tracking)
secalert@redhat.com

Frequently asked questions

What is CVE-2026-12528?: CVE-2026-12528 is a medium-severity vulnerability in Red Hat Directory Server 11, classified under Out-of-bounds Write. CVSS score: 5.4/10. Published 2026-06-17.
How severe is CVE-2026-12528?: Medium severity. CVSS v3 base score is 5.4 out of 10.