How severe is CVE-2021-3048?

CVE-2021-3048 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2021-3048 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-3048?

CVE-2021-3048 affects Paloaltonetworks Pan-os. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2021-3048?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-3048 published?

CVE-2021-3048 was published on 2021-08-11 and last updated on 2026-06-17.

CVE-2021-3048

CVE-2021-3048 is a medium-severity vulnerability in Paloaltonetworks Pan-os with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
CVSS v2: 4.3
EPSS exploit prediction: 1% (54th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Paloaltonetworks Pan-os
Published: 2021-08-11
Last modified: 2026-06-17

Description

Certain invalid URL entries contained in an External Dynamic List (EDL) cause the Device Server daemon (devsrvr) to stop responding. This condition causes subsequent commits on the firewall to fail and prevents administrators from performing commits and configuration changes even though the firewall remains otherwise functional. If the firewall then restarts, it results in a denial-of-service (DoS) condition and the firewall stops processing traffic. This issue impacts: 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. PAN-OS 8.1 and PAN-OS 10.1 versions are not impacted.

Frequently asked questions

What is CVE-2021-3048?: Certain invalid URL entries contained in an External Dynamic List (EDL) cause the Device Server daemon (devsrvr) to stop responding. This condition causes subsequent commits on the firewall to fail and prevents administrators from performing commits and configuration changes even though the firewall remains otherwise functional. If the firewall then restarts, it results in a denial-of-service (DoS) condition and the firewall stops processing traffic. This issue impacts: 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. PAN-OS 8.1 and PAN-OS 10.1 versions are not impacted.
How severe is CVE-2021-3048?: CVE-2021-3048 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2021-3048 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-3048?: CVE-2021-3048 affects Paloaltonetworks Pan-os. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2021-3048?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-3048 published?: CVE-2021-3048 was published on 2021-08-11 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:paloaltonetworks:pan-os:*:*:*:*:*:*:*:*

More vulnerabilities in Paloaltonetworks Pan-os

CVE-2024-3400 — Critical (CVSS 10.0): A command injection as a result of arbitrary file creation vulnerability in the GlobalProtect feature of Palo Alto…
CVE-2020-2021 — Critical (CVSS 10.0): When Security Assertion Markup Language (SAML) authentication is enabled and the 'Validate Identity Provider…
CVE-2019-17440 — Critical (CVSS 10.0): Improper restriction of communications to Log Forwarding Card (LFC) on PA-7000 Series devices with second-generation…
CVE-2012-6603 — Critical (CVSS 10.0): The web management UI in Palo Alto Networks PAN-OS before 3.1.12, 4.0.x before 4.0.10, and 4.1.x before 4.1.4 allows…
CVE-2012-6601 — Critical (CVSS 10.0): The device-management command-line interface in Palo Alto Networks PAN-OS before 3.1.12, 4.0.x before 4.0.10, and 4.1.x…
CVE-2012-6593 — Critical (CVSS 10.0): Palo Alto Networks PAN-OS before 3.1.10 and 4.0.x before 4.0.4 allows remote attackers to execute arbitrary commands…

All CVEs affecting Paloaltonetworks Pan-os →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →