python-pillow Pillow Flaw (CVE-2026-112406) Rated CVSS 8.7
A newly published high vulnerability in python-pillow Pillow carries a CVSS score of 8.7. Here is what is affected and how to respond.
Key points
- CVE-2026-112406 affects python-pillow Pillow.
- CVSS 8.7 (High).
- No exploitation confirmed yet.
A high security flaw tracked as CVE-2026-112406 has been published in the National Vulnerability Database for python-pillow Pillow, with a CVSS base score of 8.7.
At a glance
- CVE
- CVE-2026-112406
- Product
- python-pillow Pillow
- CVSS
- 8.7 High
- Weakness
- CWE-835
- Exploited
- No known exploitation
What is the vulnerability?
The NVD entry states: Pillow is a Python imaging library. From 5.1.0 until 13.0.0, Pillow can enter an infinite loop while rewriting PDF pages. PdfParser.rewrite_pages() follows Parent relationships without detecting a cycle in the page tree. An attacker can supply a cyclic PDF to an application that appends an image to that PDF. This can hold the worker at full CPU and deny service. This issue is fixed in version 13.0.0.
Affected versions
| Vendor | Product | Versions |
|---|---|---|
| Python-Pillow | Pillow | >= 5.1.0, < 13.0.0 |
Is it being exploited?
There is no public confirmation of exploitation at the time of publication. It does not appear in CISA's Known Exploited Vulnerabilities catalog. We will update this report if that changes.
What should you do?
- Identify whether the affected product and versions run in your environment.
- Apply the vendor update listed in the advisory as soon as it is available.
- Limit network exposure of the affected service until it is patched.
- Monitor the vendor advisory for updated guidance or exploitation reports.
What to do and how to stay safe: CVE-2026-112406
- Vulnerability severity scores ignore your specific architecture and context.
- Exploitability depends on network exposure and user behavior, not just code flaws.
- Prioritization requires continuous asset inventory and threat intelligence alignment.
Risk-based vulnerability management focuses your limited resources on the flaws that actually threaten your business. Start by mapping your critical assets and checking for active exploits to prioritize your backlog.
Step-by-step guide: Risk-Based Vulnerability Management: Prioritize Fixes by Actual Danger
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-112406?
CVE-2026-112406 is a CWE-835 vulnerability in python-pillow Pillow.
How severe is CVE-2026-112406?
It has a CVSS score of 8.7 High.
Is CVE-2026-112406 being exploited?
There is no public confirmation of exploitation at the time of publication.
