---
id: CVE-2026-5263
title: >-
  URI nameConstraints from constrained intermediate CAs are parsed but not
  enforced during certificate chain verification in wolfcrypt/src/asn.c
summary: >-
  URI nameConstraints from constrained intermediate CAs are parsed but not
  enforced during certificate chain verification in wolfcrypt/src/asn.c. A
  compromised or malicious sub-CA could issue leaf certificates with URI SAN
  entries that vio…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-295
vendor: wolfssl
product: wolfssl
affected:
  - wolfssl < 5.9.1
patched:
  - wolfssl 5.9.1
published: '2026-04-09'
updated: '2026-07-02'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-5263'
references:
  - url: 'https://github.com/wolfSSL/wolfssl/pull/10048'
    label: facts@wolfssl.com
  - url: 'https://www.talosintelligence.com/vulnerability_reports/TALOS-2026-2410'
    label: af854a3a-2127-422b-91ae-364da2661108
tags:
  - nvd
epss: 0.00172
epssPercentile: 0.06984
ingestedAt: '2026-07-02T15:38:24.958Z'
---

## Overview

URI nameConstraints from constrained intermediate CAs are parsed but not enforced during certificate chain verification in wolfcrypt/src/asn.c. A compromised or malicious sub-CA could issue leaf certificates with URI SAN entries that violate the nameConstraints of the issuing CA, and wolfSSL would accept them as valid.

## Affected

- `wolfssl < 5.9.1`

## Remediation

Upgrade past the affected range:

- `wolfssl 5.9.1`