wolfSSL up to 5.9.1 wolfSSL_X509_verify_cert certificate validation

CVSS Meta Temp Score
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CTI Interest Score
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3.7$0-$5k0.00

Summaryinfo

A vulnerability, which was classified as problematic, was found in wolfSSL up to 5.9.1. This vulnerability affects the function wolfSSL_X509_verify_cert. Such manipulation leads to certificate validation. This vulnerability is referenced as CVE-2026-11999. It is possible to launch the attack remotely. No exploit is available.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in wolfSSL up to 5.9.1. Affected by this issue is the function wolfSSL_X509_verify_cert. The manipulation with an unknown input leads to a certificate validation vulnerability. Using CWE to declare the problem leads to CWE-295. The product does not validate, or incorrectly validates, a certificate. Impacted is integrity. CVE summarizes:

X.509 trust-chain bypass (path-depth exhaustion) in the OpenSSL compatibility certificate verifier (wolfSSL_X509_verify_cert()). This affects only builds with --enable-opensslextra whose application calls X509_verify_cert() with caller-supplied untrusted intermediates; for those users it is critical, otherwise the library is unaffected. Native wolfSSL TLS/DTLS usage is not impacted. X509_verify_cert() returned success based only on the last verified link rather than on reaching a trust anchor: when the supplied chain is deeper than the verifier's maximum path depth (default 100), path building runs out of depth while still walking untrusted intermediates and the chain is accepted even though it never reaches a configured trust anchor, allowing acceptance of an attacker-controlled certificate. The default TLS handshake (WOLFSSL_VERIFY_PEER) is not affected; only applications doing manual or deferred verification through this API are.

The weakness was published by Corban Villa, Sohee Kim and Austin Chu. The advisory is available at github.com. This vulnerability is handled as CVE-2026-11999 since 06/11/2026. The exploitation is known to be difficult. The attack may be launched remotely. No form of authentication is required for exploitation. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 07/01/2026). This vulnerability is assigned to T1587.003 by the MITRE ATT&CK project.

The vulnerability scanner Nessus provides a plugin with the ID 323799 (Linux Distros Unpatched Vulnerability : CVE-2026-11999), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at Tenable (323799). If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 3.7
VulDB Meta Temp Score: 3.7

VulDB Base Score: 3.7
VulDB Temp Score: 3.7
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Certificate validation
CWE: CWE-295 / CWE-287
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 323799
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-11999

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

06/11/2026 CVE reserved
06/25/2026 +14 days Advisory disclosed
06/25/2026 +0 days VulDB entry created
07/01/2026 +6 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Researcher: Corban Villa, Sohee Kim, Austin Chu
Status: Confirmed

CVE: CVE-2026-11999 (🔒)
GCVE (CVE): GCVE-0-2026-11999
GCVE (VulDB): GCVE-100-373970

Entryinfo

Created: 06/25/2026 19:35
Updated: 07/01/2026 21:55
Changes: 06/25/2026 19:35 (65), 07/01/2026 21:55 (2)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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