Palo Alto Networks
Threat Brief: Active Exploitation of PAN-OS CVE-2026-0257 (Updated October 19)
At a glance
Actively exploited in the wild — prioritise confirming exposure.
High rather than Critical: exposure is scored at a default because we cannot see your systems or suppliers. If you run or depend on Palo Alto Networks PAN-OS, treat it as Critical.
Briefing
- Organisations using Palo Alto Networks PAN-OS should verify if they are affected by CVE-2026-0257.
Questions to ask IT
- Do we run Palo Alto Networks PAN-OS, and which versions?
- Is any of it reachable from the internet?
- Have we checked whether it has already been used against us?
- If it is still not patched, what mitigation is in place, and what is holding the fix up?
Next steps
- Confirm exposure and remediation status for affected products
Vulnerability facts
Full CVE detail CVE-2026-0257- 7.8 · HighExploitable over the network without any account, and no one has to click or open anything. High impact on subsequent confidentiality and subsequent integrity; low on confidentiality.CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:H/SI:H/SA:N/E:A/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:N/R:A/V:D/RE:M/U:Red
- Listed: attacks using it have been seen
- Elevated attack likelihood (~95.6% in 30 days)
- The vulnerability affects Palo Alto Networks PAN-OS and is classified as an authentication bypass.
Next steps
- Confirm whether affected products/versions are present and prioritise patching or mitigations
Summary
- Palo Alto Networks PAN-OS has a confirmed authentication bypass vulnerability identified as CVE-2026-0257.
- CVE-2026-0257 is reported to be actively exploited in the wild according to the US known-exploited catalogue.
Products and services involved
- Palo Alto Networks PAN-OS93% match confidence · CVE-2026-0257
Part of The PHP2Shell disclosure
Pulse
Last checked 3d ago · Recheck overdue since 6 Nov 2026, 11:38 UK time
- Story20 Oct 2026, 17:09 UK time · 20 Oct
Linked reporting from Unit 42 (independent original reporter).
Read source (Unit 42) - Signal5 Nov 2026, 11:38 UK time · 3d ago
in the next 30 days first recorded at 95.6% (elevated likelihood signal, not confirmed exploitation).
2 entries so far. The timeline chart appears once this story has more history.
Sources
Threat Brief: Active Exploitation of PAN-OS CVE-2026-0257 (Updated October 19)
How we know
Statements extracted from sources. Higher confidence means stronger corroboration.
- ClaimedHeadline60% confidence
Palo Alto Networks PAN-OS Authentication Bypass Vulnerability
- ConfirmedCVE identifier95% confidence
Event involves CVE-2026-0257
- ConfirmedKnown-exploited catalogue98% confidence
CVE-2026-0257 is confirmed as exploited in the wild (US known-exploited catalogue)