CyberSecBulletin
CVE-2026-25990NVD status: Modified

Pillow: Out-of-bounds Write

CVE-2026-25990 is a high-severity out-of-bounds write vulnerability in Pillow from Python-pillow, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Pillow versions: >= 10.3.0, < 12.1.1. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.4% 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. Check which version of Pillow you run against the affected versions below, and install the vendor's latest release.
  2. Read the advisory on github.com for workarounds and exact fixed builds.
  3. 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
Python-pillowPillow>= 10.3.0, < 12.1.1Not stated
Red HatRed Hat Ansible Automation Platform 2.5 for RHEL 8Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.5 for RHEL 9Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.6 for RHEL 9Not specified in the recordNot stated
Red HatRed Hat Satellite 6.16 for RHEL 8Not specified in the recordNot stated
Red HatRed Hat Satellite 6.16 for RHEL 9Not specified in the recordNot stated
Red HatRed Hat Satellite 6.17 for RHEL 9Not specified in the recordNot stated
Red HatRed Hat Satellite 6.18 for RHEL 9Not specified in the recordNot stated
Red HatRed Hat AI Inference Server 3.2Not specified in the recordNot stated
Red HatRed Hat AI Inference Server 3.3Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.5Not specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2.6Not specified in the recordNot stated
Red HatRed Hat OpenShift AI 2.25Not specified in the recordNot stated
Red HatRed Hat OpenShift AI 3.3Not specified in the recordNot stated
Red HatRed Hat Quay 3.10Not specified in the recordNot stated
Red HatRed Hat Quay 3.12Not specified in the recordNot stated
Red HatRed Hat Quay 3.15Not specified in the recordNot stated
Red HatRed Hat Quay 3.16Not specified in the recordNot stated
Red HatRed Hat Quay 3.9Not specified in the recordNot stated
Red HatOpenShift LightspeedNot specified in the recordNot stated
Red HatRed Hat AI Inference ServerNot specified in the recordNot stated
Red HatRed Hat Ansible Automation Platform 2Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 7Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux 8Not specified in the recordNot stated
Red HatRed Hat Enterprise Linux AI (RHEL AI) 3Not specified in the recordNot stated

Version data comes from the organisation that assigned the CVE; 2 further products are omitted here. 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
UnchangedImpact stays within the vulnerable component.
Confidentiality
NoneNo data is disclosed.
Integrity
NoneNothing can be modified.
Availability
HighThe component can be taken down completely.

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

Scoring systemScoreSeverityScored by
CVSS 4.08.6HighCNA (github.com)
CVSS 3.17.5HighNVD
CVSS 3.17.3HighCNA

Official description

Pillow is a Python imaging library. From 10.3.0 to before 12.1.1, an out-of-bounds write may be triggered when loading a specially crafted PSD image. This vulnerability is fixed in 12.1.1.

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

The underlying weakness: Out-of-bounds Write

The product writes data past the end, or before the beginning, of the intended buffer.

How developers prevent this class of flaw

  • Use a language that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, many languages that perform their own memory management, such as Java and Perl, are not subject to buffer overflows. Other languages, such as Ada and C#, typically provide overflow protection, but the protection can be disabled by the programmer. Be wary that a language's interface to native code may still be subject to overflows, even if the language itself is theoretically safe.
  • Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. Examples include the Safe C String Library (SafeStr) by Messier and Viega, and the Strsafe.h library from Microsoft. These libraries provide safer versions of overflow-prone string-handling functions.
  • Use automatic buffer overflow detection mechanisms that are offered by certain compilers or compiler extensions. Examples include: the Microsoft Visual Studio /GS flag, Fedora/Red Hat FORTIFY_SOURCE GCC flag, StackGuard, and ProPolice, which provide various mechanisms including canary-based detection and range/index checking. D3-SFCV (Stack Frame Canary Validation) from D3FEND discusses canary-based detection in detail.

More Out-of-bounds Write vulnerabilities (CWE-787)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in Pillow

All Pillow vulnerabilities

Recent Out-of-bounds Write vulnerabilities

Spotted an error? Tell us.