PT-2026-6308 · Cert Manager · Cert-Manager

1Seal · Published 2026-02-02 · Updated 2026-05-21 · CVE-2026-25518

Positive Technologies (AI Summary)

CVSS v3.1

9.8

Critical

Base vector

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

Name of the Vulnerable Software and Affected Versions cert-manager versions 1.18.0 through 1.18.4 cert-manager versions 1.19.0 through 1.19.2

Description cert-manager simplifies the process of obtaining, renewing, and using certificates in Kubernetes clusters. The cert-manager-controller performs DNS lookups during ACME DNS-01 processing, which by default use unencrypted DNS. An attacker intercepting and modifying DNS traffic to the cert-manager-controller pod can insert a crafted entry into cert-manager’s DNS cache. Accessing this entry causes a panic, leading to a denial-of-service (DoS) condition of the cert-manager controller. Exploitation is also possible if a malicious actor controls the authoritative DNS server for the validated domain.

Recommendations Update to cert-manager version 1.18.5 or later. Update to cert-manager version 1.19.3 or later.

Exploit

Fix

Incorrect Type Conversion or Cast

Improper Validation of Array Index

Weakness Enumeration

CWE-704

CWE-129

Related Identifiers

BIT-CERT-MANAGER-2026-25518

CLEANSTART-2026-AC65885

CLEANSTART-2026-BB70412

CLEANSTART-2026-GZ35045

CLEANSTART-2026-OL32822

CLEANSTART-2026-TZ92532

CLEANSTART-2026-VZ35122

CVE-2026-25518

GHSA-GX3X-VQ4P-MHHV

GO-2026-4399

SUSE-SU-2026:0757-1

Affected Products

Cert-Manager

References · 232

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/25xxx/CVE-2026-25518.json · Exploit
• https://github.com/cert-manager/cert-manager/pull/8468 · Patch
• https://github.com/cert-manager/cert-manager/pull/8469 · Patch
• https://github.com/cert-manager/cert-manager/commit/d4faed26ae12115cceb807cdc12507ebc28980e2 · Patch
• https://github.com/cert-manager/cert-manager/commit/409fc24e539711a07aae45ed45abbe03dfdad2cc · Patch
• https://github.com/cert-manager/cert-manager/commit/9a73a0b3853035827edd37ac463e4803ba10327d · Patch
• https://github.com/cert-manager/cert-manager/pull/8467 · Patch
• https://github.com/cert-manager/cert-manager/security/advisories/GHSA-gx3x-vq4p-mhhv · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-68119 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2025-68121 · Security Note
• https://osv.dev/vulnerability/CLEANSTART-2026-OL32822 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-39836 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2026-27143 · Security Note
• https://osv.dev/vulnerability/CLEANSTART-2026-TZ92532 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-61728 · Security Note