HOMEVULNERABILITIESCVE-2026-5263
HIGHPOC

CVE-2026-5263

CWE-295Published: April 9, 2026· Updated: Apr 13, 2026

7.0
CVSS v3.1
EPSS:0.02%probability of exploitation in 30 daysPercentile:5.5th

Official Description

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.

NVD Source

Technical Analysis

CVE-2026-5263 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires high privileges, which limits the exposure to scenarios where an attacker has already gained initial access.

A proof-of-concept (PoC) exploit exists for CVE-2026-5263. While not yet confirmed in active campaigns, the availability of PoC code increases exploitation risk substantially.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.High
User InteractionNone
ScopeX
Impact
Confidentiality
Integrity
Availability
CVSS:4.0/AV:N/AC:L/AT:P/PR:H/UI:N/VC:H/VI:L/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Exploit & PoC Resources

POC AVAILABLEProof-of-concept code exists
External links open in a new tab. Always verify in a controlled environment before use.

All References (1)

Quick Facts

CVE IDCVE-2026-5263
CVSS Score7.0 / 10
SeverityHIGH
WeaknessCWE-295
CISA KEVNo
ExploitPOC
EPSS (30d)0.02%
PublishedApr 9, 2026

Related CVEs (CWE-295)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2026-5263 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.