Medium Cross-site scripting

CVE-2026-0279 — PAN-OS: Multiple Cross-Site Scripting (XSS) Vulnerabilities

Multiple cross site scripting vulnerabilities in the User-ID™ Authentication Portal (aka Captive Portal) service, GlobalProtect™ gateway/portal features and Clientless VPN of Palo Alto Networks PAN-OS® software enables a malicious unauthenticated user to store or execute malicious JavaScript payload. The security risk posed by this issue is minimized when the management interface and access to the User-ID™ Authentication Portal is restricted to only trusted internal IP addresses according to our recommended best practice deployment guidelines https://live.paloaltonetworks.com/t5/community-blogs/tips-amp-tricks-how-to-secure-the-management-access-of-your-palo/ba-p/464431 . This issue is applicable to PAN-OS software on PA-Series and VM-Series firewalls and on Panorama (virtual and M-Series). Cloud NGFW is not affected by this vulnerability.

Published Jul 9, 2026 · Updated Oct 15, 2026 · Sources: CVE Program (cve.org) e CISA ADP, NIST National Vulnerability Database · CNA: palo_alto

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.8% (30-day exploitation probability)+8
Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.75%

ahead of 54% of scored CVEs · Oct 14, 2026

Affects

Palo Alto Networks

PAN-OS and 1 more

CVSS base

6.1

Medium · 3 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation

None

none · proof-of-concept · active

Automatable

can an attacker script the kill-chain steps

Technical impact

Partial

partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Palo Alto Networks PAN-OS, Palo Alto Networks Prisma Access).
The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Exploitation requires user interaction: tighten email/web filtering and warn affected users.
Search available logs for exploit probes matching the vulnerability class (cross-site scripting), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Palo Alto Networks	PAN-OS	≥ 12.1.0 and < 12.1.8≥ 11.2.0 and < 11.2.13≥ 11.1.0 and < 11.1.16≥ 10.2.0 and < 10.2.18-h8	Vulnerable	CVE Program (cve.org) e CISA ADP
Palo Alto Networks	PAN-OS	≥ 10.2.0 and < 11.1.16≥ 11.2.0 and < 11.2.13≥ 12.1.0 and < 12.1.8	Vulnerable	NIST National Vulnerability Database
Palo Alto Networks	Prisma Access	≥ 12.1.0 and < 12.1.8version 11.2.0version 10.2.0	Vulnerable	CVE Program (cve.org) e CISA ADP

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector

Network

Attack complexity

Low

Privileges required

None

User interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

Score	Version	Severity	Expl.	Impact	Scored by
1.3	CVSS 4.0	Low	—	—	psirt@paloaltonetworks.com via NIST National Vulnerability Database
1.3	CVSS 4.0	Low	—	—	palo_alto via CVE Program (cve.org) e CISA ADP
1.2	CVSS 4.0	Low	—	—	palo_alto via CVE Program (cve.org) e CISA ADP
0.4	CVSS 4.0	Low	—	—	palo_alto via CVE Program (cve.org) e CISA ADP
6.1	CVSS 3.1	Medium	2.8	2.7	nvd@nist.gov via NIST National Vulnerability Database

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N (score shown at the top: nvd@nist.gov)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-79 · Cross-site Scripting (XSS)

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
Monitor CSP violation reports and script payloads in reflected parameters.

web/proxy/WAF logsnetwork IDS/IPSapplication logs

Timeline

What happened to this CVE, newest first.

2026
Affected products added · paloaltonetworks/pan-os
Oct 15, 2026 · NIST National Vulnerability Database
CVSS changed · 1.3 → 6.1
Oct 15, 2026 · NIST National Vulnerability Database
Source status changed · Published → Modified
Oct 15, 2026 · NIST National Vulnerability Database
Record published
Oct 15, 2026
CVSS changed · 1.3
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Published
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
SSVC assessment updated
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Record created in this database
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
CVE published
Jul 9, 2026 · palo_alto

Source activity

Repeated readings are counted rather than listed.

1× References added · Oct 15, 2026 – Oct 15, 2026
1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

2 on the record

security.paloaltonetworks.com/CVE-2026-0279
vendor-advisory, Vendor Advisory, CVE Program (cve.org) e CISA ADP
cert-portal.siemens.com/productcert/html/ssa-104023.html
NIST National Vulnerability Database

Elsewhere on this site

Palo Alto Networks
every CVE for this vendor

Cross-site scripting
same class

CWE-79
other pages naming this weakness

Related CVEs (same products)

Medium CVE-2026-0320 PAN-OS: Authenticated Admin Command Injection Vulnerability 1d
Medium CVE-2026-0318 PAN-OS: Denial of Service (DoS) on Panorama 1d
Medium CVE-2026-0319 PAN-OS: Improper Input Handling Vulnerability 1d
Low CVE-2026-0317 PAN-OS: Denial of Service Vulnerability 1d
Low CVE-2026-0316 PAN-OS: Stored Cross-Site Scripting (XSS) Vulnerability 1d
Medium CVE-2026-0321 PAN-OS: Denial of Service (DoS) Vulnerabilities in Network Services 1d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No fixed version, patch or mitigation documented.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-0279 is "PAN-OS: Multiple Cross-Site Scripting (XSS) Vulnerabilities", rated Medium. It affects PAN-OS (Palo Alto Networks); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.1 describes technical severity. EPSS 0.75% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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