CyberSecBulletin
CVE-2026-0280NVD status: Modified

Cloud NGFW: Incorrect Calculation of Buffer Size

CVE-2026-0280 is a high-severity incorrect calculation of buffer size vulnerability in Cloud NGFW from Palo Alto Networks, with a CVSS 3.1 base score of 7.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. There is no confirmed exploitation so far. EPSS estimates a 0.34% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update PAN-OS to 12.1.8 or 11.2.13 or 11.1.16 or 10.2.18-h8, whichever matches your release line, or a later version.
  2. Update Prisma Access to 11.2.7-h18 or 10.2.10-h39, whichever matches your release line, or a later version.
  3. Read the advisory on security.paloaltonetworks.com for workarounds and exact fixed builds.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Palo Alto NetworksCloud NGFWNot specified in the recordNot stated
Palo Alto NetworksPAN-OS12.1.0 up to, but not including, 12.1.8; 11.2.0 up to, but not including, 11.2.13; 11.1.0 up to, but not including, 11.1.16; 10.2.0 up to, but not including, 10.2.18-h812.1.8, 11.2.13, 11.1.16, 10.2.18-h8
Palo Alto NetworksPanoramaNot specified in the recordNot stated
Palo Alto NetworksPrisma Access11.2.0 up to, but not including, 11.2.7-h18; 10.2.0 up to, but not including, 10.2.10-h3911.2.7-h18, 10.2.10-h39
SiemensRUGGEDCOM APE1808all versionsNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
LowSome restricted data can be read.
Integrity
LowLimited modification of data is possible.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 4.01.7LowCNA (paloaltonetworks.com)
CVSS 3.17.2HighNVD

Official description

An IPv6 packet processing vulnerability in the dataplane of Palo Alto Networks PAN-OS® software enables an unauthenticated attacker to bypass firewall security policy enforcement, allowing network traffic that should be blocked to reach protected services. Cloud NGFW and Panorama are not impacted by this vulnerability.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Incorrect Calculation of Buffer Size

The product does not correctly calculate the size to be used when allocating a buffer.

How developers prevent this class of flaw

  • When allocating a buffer for the purpose of transforming, converting, or encoding an input, allocate enough memory to handle the largest possible encoding. For example, in a routine that converts & characters to & for HTML entity encoding, the output buffer needs to be at least 5 times as large as the input buffer.
  • Understand the programming language's underlying representation and how it interacts with numeric calculation (CWE-681). Pay close attention to byte size discrepancies, precision, signed/unsigned distinctions, truncation, conversion and casting between types, not-a-number calculations, and how the language handles numbers that are too large or too small for its underlying representation. Also be careful to account for 32-bit, 64-bit, and other potential differences that may affect the numeric representation.
  • Perform input validation on any numeric input by ensuring that it is within the expected range. Enforce that the input meets both the minimum and maximum requirements for the expected range.

More Incorrect Calculation of Buffer Size vulnerabilities (CWE-131)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Cloud NGFW

All Cloud NGFW vulnerabilities

Recent Incorrect Calculation of Buffer Size vulnerabilities

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