CVE-2021-3055 json
PAN-OS: XML External Entity (XXE) Reference Vulnerability in the PAN-OS Web Interface
published 2021-09-08 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-26407
- cvss
- 6.5
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.1%
- EPSS 1.1% chance of exploitation in 30 days, percentile 65%
- public exploits
- 0
- none known
Summary
An improper restriction of XML external entity (XXE) reference vulnerability in the Palo Alto Networks PAN-OS web interface enables an authenticated administrator to read any arbitrary file from the file system and send a specifically crafted request to the firewall that causes the service to crash. Repeated attempts to send this request result in denial of service to all PAN-OS services by restarting the device and putting it into maintenance mode. This issue impacts: PAN-OS 8.1 versions earlier than PAN-OS 8.1.20; PAN-OS 9.0 versions earlier than PAN-OS 9.0.14; PAN-OS 9.1 versions earlier than PAN-OS 9.1.10; PAN-OS 10.0 versions earlier than PAN-OS 10.0.6. This issue does not affect Prisma Access.
Patch / fix
- Palo Alto Networks PAN-OS 8.1.20, 9.0.14, 9.1.10, 10.0.6
Exploit prediction
1.07% chance of exploitation in the next 30 days, higher than 65% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H |
| NVD | 3.1 | 6.5 | CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:S/C:P/I:N/A:C |
Affected products
- Palo Alto Networks PAN-OS
Classification
- Weakness
-
- CWE-611 Improper Restriction of XML External Entity Reference
- Technology feeds
References
-
security.paloaltonetworks.com
/CVE-2021-3055
vendor-advisory
Sources
- CVE List CVE-2021-3055
- NVD CVE-2021-3055
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