This report was translated by AI; nobody has reviewed the translation yet. Original language: Czech.

[TLP:CLEAR] Palo Alto PAN-OS fixes an actively exploited vulnerability

Palo Alto fixes a critical, actively exploited vulnerability in PAN-OS (PA-Series and VM-Series firewalls). The relevant fixes are expected to be released on 13 and 28 May 2026, see [1]. Fixed versions of the product: PAN-OS 12.1 - 12.1.4-h5, 12.1.7 PAN-OS 11.2 - 11.2.4-h17, 11.2.7-h13, 11.2.10-h6, 11.2.12 PAN-OS 11.1 - 11.1.4-h33, 11.1.6-h32, 11.1.7-h6, 11.1.10-h25, 11.1.13-h5, 11.1.15 PAN-OS 10.2 - 10.2.7-h34, 10.2.10-h36, 10.2.13-h21, 10.2.16-h7, 10.2.18-h6

Palo Alto PAN-OS - privilege escalation, RCE (CVE-2026-0300)
CVSS 9.3 (Critical)

An unauthenticated remote attacker can execute code with root privileges on PA-Series and VM-Series firewalls due to a stack overflow [1]. The risk can be temporarily mitigated by restricting access to the User-ID™ Authentication Portal to trusted internal IP addresses only, or by disabling it entirely if it is not needed. Hardening instructions can be found in item 6 at [2] and at [3].

The vulnerability is present in product:

  • PAN-OS; >=10.2.7, <10.2.7-h34; >=10.2.10, <10.2.10-h36; >=10.2.13, <10.2.13-h21; >=10.2.16, <10.2.16-h7; >=10.2.18, <10.2.18-h6; >=11.1.4, <11.1.4-h33; >=11.1.6, <11.1.6-h32; >=11.1.7, <11.1.7-h6; >=11.1.10, <11.1.10-h25; >=11.1.13, <11.1.13-h5; >=11.2.4, <11.2.4-h17; >=11.2.7, <11.2.7-h13; >=11.2.10, <11.2.10-h6; >=12.1.4, <12.1.4-h5;

CVSS: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N/E:A/AU:Y/R:U/V:C/RE:M/U:Red

More information:

The vulnerability was publicly disclosed 6. 5. 2026.

By CESNET, z.s.p.o. Michaela Ručková on 6. 5. 2026.

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