← Vulnerability feed

Vulnerability record · CVE-2026-12528 · published 17 June 2026

CVE-2026-12528: Redhat directory server out-of-bounds write vulnerability

Redhat · Directory Server

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.

5.4 CVSS 3.1 Medium EPSS 0.23% · top 88.0% CWE-787 · Out-of-bounds write
5.4CVSS 3.1 base score
0.23%EPSS exploitation probability, 30 days
NoNot in CISA KEV
3Affected product versions listed by NVD
3References
28 Jun 2026Last modified by NVD

Description

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.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L

Affected products

3 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://access.redhat.com/security/cve/CVE-2026-12528 Vendor Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=2489835 Issue TrackingVendor Advisory
https://github.com/389ds/389-ds-base/pull/7542 Patch

Track CVE-2026-12528 inside VULONE

Watch it alongside the ransomware crews, C2 infrastructure and forum chatter that reference it, query it through the API and pull it into your SIEM over TAXII.

Start free Open in platform

Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

9.8CVE-2019-11043PHP-FPM buffer overflow enables remote code executionPHP-FPM in certain configurations writes past allocated buffers into FCGI protocol data space, an out-of-bounds write (CWE-787, CWE-120). It affects …KEVEPSS 100%analysed9.8CVE-2018-14667RichFaces Framework EL injection enables unauthenticated remote code executionRichFaces Framework 3.X through 3.3.4 is vulnerable to Expression Language injection through the UserResource resource. A remote, unauthenticated att…KEVEPSS 74%analysed9.8CVE-2014-7169GNU Bash environment variable function parsing command injection (Shellshock variant)GNU Bash through 4.3 bash43-025 processes trailing strings after malformed function definitions in environment variable values, allowing command inje…KEVEPSS 100%analysed9.8CVE-2014-6271GNU Bash environment variable command injection (ShellShock)GNU Bash through 4.3 processes trailing strings after function definitions in environment variable values, allowing injected commands to run when Bas…KEVEPSS 100%analysed9.0CVE-2021-40438Apache HTTP Server mod_proxy SSRF via crafted URI pathA crafted request URI path can make mod_proxy forward the request to an origin server chosen by the remote user, an SSRF flaw in Apache HTTP Server 2…KEVEPSS 100%analysed8.8CVE-2025-31277Apple WebKit memory corruption via malicious web contentApple WebKit fails to handle memory correctly when processing crafted web content, leading to memory corruption across Safari, iOS, iPadOS, macOS, tv…KEVEPSS 1.6%analysed8.8CVE-2023-5217libvpx VP8 encoding heap buffer overflow exploited via crafted HTMLA heap buffer overflow in the VP8 encoder in libvpx affects Google Chrome before 117.0.5938.132 and libvpx 1.13.1, and is reachable through a crafted…KEVEPSS 49%analysed8.8CVE-2023-32373Apple WebKit use-after-free enables code execution via web contentA use-after-free flaw in Apple's WebKit engine was fixed across watchOS, tvOS, macOS, iOS, iPadOS and Safari. Processing maliciously crafted web cont…KEVEPSS 12%analysed

Source: NIST National Vulnerability Database (record CVE-2026-12528), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.