CVE-2021-3053
PAN-OS: Exceptional Condition Denial-of-Service (DoS)
- Published
- Updated
- Reserved
- Assigned by
- palo_alto
Description
An improper handling of exceptional conditions vulnerability exists in the Palo Alto Networks PAN-OS dataplane that enables an unauthenticated network-based attacker to send specifically crafted traffic through 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 9.1.9; PAN-OS 10.0 versions earlier than PAN-OS 10.0.5. This issue does not affect Prisma Access.
Timeline
ID reserved
By palo_alto
- 8 months later
· 8 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| palo_altoCNA (assigner) | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 1.0% · top 37% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.
Weakness
Affected products
- unaffected 10.1.*
- affected 8.1 – < 8.1.20
- affected 9.0 – < 9.0.14
- affected 9.1 – < 9.1.9
- affected 10.0 – < 10.0.5
What to do
Solution: This issue is fixed in PAN-OS 8.1.20, PAN-OS 9.0.14, PAN-OS 9.1.9, PAN-OS 10.0.5, and all later PAN-OS versions.
Workaround: There are no known workarounds for this issue.
Exploitation: Palo Alto Networks is not aware of any malicious exploitation of this issue.
References (1)
- https://security.paloaltonetworks.com/CVE-2021-3053 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-3053)Record last updated .