Vulnerability · Published Oct 19, 2026 · Assigned by GitHub_M
CVE-2026-112391Pillow: PdfParser can recurse without limit in get_value() and linearize_page_tree()
Medium 6.3
In plain English
A medium-severity infinite loop in Pillow from python-pillow. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 48% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Pillow is a Python imaging library. From 5.1.0 until 13.0.0, Pillow's PdfParser.get_value() can recurse without a limit while reading nested PDF objects. The parser follows attacker-controlled arrays and dictionaries when an existing PDF is opened for append. An attacker can provide a deeply nested PDF to an application that saves an image with PDF append enabled. This can raise an uncaught RecursionError or terminate the worker, causing denial of service. This issue is fixed in version 13.0.0.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux:8 | python3-pillow | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| AlmaLinux:8 | python3-pillow-devel | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| AlmaLinux:8 | python3-pillow-doc | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| AlmaLinux:8 | python3-pillow-tk | 5.1.1-33.el8_10 | ALSA-2026:92639 |
| Debian:12 | pillow | no fix listed | DEBIAN-CVE-2026-112391 |
| Debian:13 | pillow | no fix listed | DEBIAN-CVE-2026-112391 |
| Debian:14 | pillow | no fix listed | DEBIAN-CVE-2026-112391 |
| PyPI | pillow | 13.0.0 | GHSA-254f-3936-288h |
| Rocky Linux:8 | python-pillow | 0:5.1.1-33.el8_10 | RLSA-2026:92639 |
| Ubuntu:22.04:LTS | pillow | no fix listed | UBUNTU-CVE-2026-112391 |
| Ubuntu:24.04:LTS | pillow | no fix listed | UBUNTU-CVE-2026-112391 |
| Ubuntu:26.04:LTS | pillow | no fix listed | UBUNTU-CVE-2026-112391 |
| Ubuntu:26.10 | pillow | no fix listed | UBUNTU-CVE-2026-112391 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| python-pillow | Pillow | >= 5.1.0, < 13.0.0 |
Weakness: CWE-835 · Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N