CVE-2026-0257: in the CISA KEV catalogue
Palo Alto Networks PAN-OS Authentication Bypass Vulnerability. CISA added CVE-2026-0257 to the Known Exploited Vulnerabilities catalogue on 2026-05-29 with a default due date of 2026-06-01. Known ransomware campaign use: Known. Forensic triage flag: No.
Palo Alto Networks PAN-OS contains an authentication bypass vulnerability that allows attackers to bypass security restrictions and establish an unauthorized VPN connection. (CISA description)
- Vendor / product
- Palo Alto Networks PAN-OS
- CWE
- CWE-565
- CISA required action
- Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
- EPSS
- 96%, percentile 99 (scored 2026-11-03)
EPSS puts about 96 in 100 odds (96%) on exploitation activity being observed in the next 30 days. Its score is higher than or equal to that of 99% of scored CVEs. This is a model estimate about exploitation anywhere, not about your environment.
Vendor and reference links (from CISA)
Your own deadline under CISA BOD 26-04 depends on exposure, automatability and technical impact: work it out with the BOD 26-04 calculator.
Frequently asked questions
Is CVE-2026-0257 in the CISA KEV catalogue?
Yes. CISA added CVE-2026-0257 (Palo Alto Networks PAN-OS Authentication Bypass Vulnerability) to the Known Exploited Vulnerabilities catalogue on 2026-05-29. CISA's default due date for it is 2026-06-01.
Is CVE-2026-0257 used in ransomware attacks?
CISA marks known ransomware campaign use as Known for CVE-2026-0257.
What should I do about CVE-2026-0257?
CISA's required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.
Sources
- CISA, Known Exploited Vulnerabilities Catalog (accessed 2026-11-03)
- FIRST, Exploit Prediction Scoring System (EPSS) (EPSS by FIRST; scores generated by Empirical Security)
- NVD record for CVE-2026-0257