CVE-2026-0264 PAN-OS: Heap-Based Buffer Overflow in DNS Proxy and DNS Server Allows Unauthenticated Remote Code Execution
Description
A buffer overflow vulnerability in the DNS proxy and DNS Server features of Palo Alto Networks PAN-OS® Software allows an unauthenticated attacker with network access to cause a denial of service (DoS) condition (all PAN-OS platforms except Cloud NGFW and Prisma Access) or potentially execute arbitrary code by sending specially crafted network traffic (PA-Series hardware only).
Panorama, Cloud NGFW, and Prisma® Access are not impacted by this vulnerability.
Product Status
| Versions | Affected | Unaffected |
|---|---|---|
| Cloud NGFW | None on AWS None on Azure unless you have been contacted by Palo Alto Networks | All on AWS All on Azure unless you have been contacted by Palo Alto Networks |
| PAN-OS 12.1 | < 12.1.4-h5 < 12.1.7 | >= 12.1.4-h5 >= 12.1.7 (ETA: 05/28) |
| PAN-OS 11.2 | < 11.2.4-h17 < 11.2.7-h13 < 11.2.10-h6 < 11.2.12 | >= 11.2.4-h17 (ETA: 05/28) >= 11.2.7-h13 >= 11.2.10-h6 >= 11.2.12 (ETA: 05/28) |
| 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 | >= 11.1.4-h33 >= 11.1.6-h32 >= 11.1.7-h6 (ETA: 05/28) >= 11.1.10-h25 >= 11.1.13-h5 >= 11.1.15 (ETA: 05/28) |
| PAN-OS 10.2 | < 10.2.7-h34 < 10.2.10-h36 < 10.2.13-h21 < 10.2.16-h7 < 10.2.18-h6 | >= 10.2.7-h34 (ETA: 05/28) >= 10.2.10-h36 >= 10.2.13-h21 (ETA: 05/28) >= 10.2.16-h7 (ETA: 05/28) >= 10.2.18-h6 |
| Prisma Access | None | All |
Required Configuration for Exposure
This issue is applicable only to PAN-OS firewalls if either of the following conditions are true:
- DNS Proxy is enabled (Network > DNS Proxy) AND a network interface is attached to DNS Proxy.
OR - The DNS server (Device > Setup > Services) configured on NGFW is a compromised public untrusted IP address.
The risk is higher if the interface is externally exposed to an untrusted network. Further documentation on configuring DNS Proxy can be found here.
Severity: HIGH, Suggested Urgency: HIGHEST
The risk is highest for PA-Series hardware firewalls as there is a potential risk of arbitrary code execution
HIGH
- CVSS-BT: 7.2 /CVSS-B: 9.2 (CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:L/SI:L/SA:N/E:U/AU:Y/R:U/V:C/RE:H/U:Red)
The risk is lower for VM-Series firewalls, as the impact is limited to a Denial of Service condition
MEDIUM
- CVSS-BT: 6.6 /CVSS-B: 8.7 (CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/AU:Y/R:A/V:D/RE:M/U:Amber)
Exploitation Status
Palo Alto Networks is not aware of any malicious exploitation of this issue.
Weakness Type and Impact
CWE-122 Heap-based Buffer Overflow
Solution
| Version | Minor Version | Suggested Solution |
|---|---|---|
| Cloud NGFW | No action needed | |
| PAN-OS 12.1 | 12.1.5 through 12.1.6 | Upgrade to 12.1.7 or later. |
| 12.1.2 through 12.1.4-h* | Upgrade to 12.1.4-h5 or 12.1.7 or later. | |
| PAN-OS 11.2 | 11.2.11 or later | Upgrade to 11.2.12 or later. |
| 11.2.8 through 11.2.10-h* | Upgrade to 11.2.10-h6 or 11.2.12 or later. | |
| 11.2.5 through 11.2.7-h* | Upgrade to 11.2.7-h13 or 11.2.12 or later. | |
| 11.2.0 through 11.2.4-h* | Upgrade to 11.2.4-h17 or 11.2.12 or later. | |
| PAN-OS 11.1 | 11.1.14 or later | Upgrade to 11.1.15 or later. |
| 11.1.11 through 11.1.13-h* | Upgrade to 11.1.13-h5 or 11.1.15 or later. | |
| 11.1.8 through 11.1.10-h* | Upgrade to 11.1.10-h25 or 11.1.15 or later. | |
| 11.1.7 through 11.1.7-h* | Upgrade to 11.1.7-h6 or 11.1.15 or later. | |
| 11.1.5 through 11.1.6-h* | Upgrade to 11.1.6-h32 or 11.1.15 or later. | |
| 11.1.0 through 11.1.4-h* | Upgrade to 11.1.4-h33 or 11.1.15 or later. | |
| PAN-OS 10.2 | 10.2.17 through 10.2.18-h* | Upgrade to 10.2.18-h6 or later. |
| 10.2.14 through 10.2.16-h* | Upgrade to 10.2.16-h7 or 10.2.18-h6 or later. | |
| 10.2.11 through 10.2.13-h* | Upgrade to 10.2.13-h21 or 10.2.18-h6 or later. | |
| 10.2.8 through 10.2.10-h* | Upgrade to 10.2.10-h36 or 10.2.18-h6 or later. | |
| 10.2.0 through 10.2.7-h* | Upgrade to 10.2.7-h34 or 10.2.18-h6 or later. | |
| Prisma Access | No action needed. | |
| All older unsupported PAN-OS versions | Upgrade to a supported fixed version. |
Workarounds and Mitigations
Customers can mitigate the risk of this issue by taking either of the following actions:
Action 1:
- Disassociate DNS Proxy from externally accessible interfaces in order to reduce your attack surface; AND
- Configure DNS server with a RFC1918 or a public trusted IP address.
- Disable the DNS Proxy feature (Network > DNS Proxy) if it is not being used; AND
- Configure DNS server with a RFC1918 or a public trusted IP address.
Customers with a Threat Prevention subscription can block attacks for this vulnerability by enabling Threat ID 510027 from Applications and Threats content version 9100-10044 and later.
Acknowledgments
CPEs
cpe:2.3:o:palo_alto_networks:pan-os:12.1.6:*:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:12.1.5:*:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:12.1.4:h3:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:12.1.4:h2:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:12.1.4:-:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:12.1.3:*:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:12.1.2:*:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:11.2.11:*:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:11.2.10:h4:*:*:*:*:*:*
cpe:2.3:o:palo_alto_networks:pan-os:11.2.10:h3:*:*:*:*:*:*
CPE Applicability
- cpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)12.1.4 and up to (excluding)12.1.4-h5
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)12.1.0 and up to (excluding)12.1.7
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.2.4 and up to (excluding)11.2.4-h17
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.2.7 and up to (excluding)11.2.7-h13
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.2.10 and up to (excluding)11.2.10-h6
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.2.0 and up to (excluding)11.2.12
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.1.4 and up to (excluding)11.1.4-h33
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.1.6 and up to (excluding)11.1.6-h32
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.1.7 and up to (excluding)11.1.7-h6
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.1.10 and up to (excluding)11.1.10-h25
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.1.13 and up to (excluding)11.1.13-h5
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)11.1.0 and up to (excluding)11.1.15
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)10.2.7 and up to (excluding)10.2.7-h34
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)10.2.10 and up to (excluding)10.2.10-h36
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)10.2.13 and up to (excluding)10.2.13-h21
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)10.2.16 and up to (excluding)10.2.16-h7
- ORcpe:2.3:o:palo_alto_networks:pan-os:*:*:*:*:*:*:*:* is vulnerable from (including)10.2.18 and up to (excluding)10.2.18-h6