Google crypto x509 up to 1.26.9/1.27.2 Denylist Verify improper check for certificate revocation

Summaryinfo

A vulnerability was found in Google crypto x509 up to 1.26.9/1.27.2. It has been classified as critical. This issue affects the function Verify of the file crypto x509 of the component Denylist. The manipulation leads to improper check for certificate revocation. This vulnerability is documented as CVE-2026-111943. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, has been found in Google crypto x509 up to 1.26.9/1.27.2. This issue affects the function Verify of the file crypto x509 of the component Denylist. The manipulation with an unknown input leads to a improper check for certificate revocation vulnerability. Using CWE to declare the problem leads to CWE-299. The product does not check or incorrectly checks the revocation status of a certificate, which may cause it to use a certificate that has been compromised. Impacted is confidentiality, integrity, and availability. The summary by CVE is:

On most platforms, Go uses the given system root certificates. However, in some narrower cases, the system trust stores may not be updated without further action. To defend against the narrower set of cases that may remain affected, a denylist was added in crypto/x509 to return an error when calling Verify with any of the known intermediate certificates that are no longer considered to be trustworthy.

The identification of this vulnerability is CVE-2026-111943 since 10/17/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 10/21/2026). The attack technique deployed by this issue is T1557.003 according to MITRE ATT&CK.

Upgrading to version 1.26.10 or 1.27.3 eliminates this vulnerability.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

• Google

Name

• crypto x509

Version

• 1.26.0
• 1.26.1
• 1.26.2
• 1.26.3
• 1.26.4
• 1.26.5
• 1.26.6
• 1.26.7
• 1.26.8
• 1.26.9
• 1.27.0
• 1.27.1
• 1.27.2

License

• free

Website

• Vendor: https://www.google.com/

CPE 2.3info

• 🔒
• 🔒
• 🔒

CPE 2.2info

• 🔒
• 🔒
• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Be aware that VulDB is the high quality source for vulnerability data.

Discussion