Description
Pillow is a Python imaging library. From 5.1.0 until 13.0.0, PdfParser.linearize_page_tree() in src/PIL/PdfParser.py treats a PDF /Pages graph as a tree without tracking duplicate indirect references. When Image.save(..., format="PDF", append=True) processes an attacker-controlled existing PDF whose /Kids arrays repeatedly reference the same child /Pages node, Pillow expands the shared subtree as distinct pages. A compact malformed PDF can therefore create exponentially many page references and consume disproportionate CPU before the append completes. This issue is fixed in version 13.0.0.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| python-pillow | Pillow | >= 5.1.0, < 13.0.0 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | pillow | No fix yet | — |
| Debian 13 | pillow | No fix yet | — |
| Debian 12 | pillow | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | pillow | 12.3.0-1ubuntu2 | USN-9064-1 |
| Ubuntu 26.04 LTS | pillow | 12.1.1-2ubuntu1.5 | USN-9064-1 |
| Ubuntu 24.04 LTS | pillow | 10.2.0-1ubuntu1.5 | USN-9064-1 |
| Ubuntu 22.04 LTS | pillow | 9.0.1-1ubuntu0.7 | USN-9064-1 |
Show 4 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | pillow | 7.0.0-4ubuntu0.9+esm2 | USN-9064-1 |
| Ubuntu Pro 20.04 LTS | pillow-python2 | No fix yet | — |
| Ubuntu Pro 18.04 LTS | pillow | 5.1.0-1ubuntu0.8+esm3 | USN-9064-1 |
| Ubuntu Pro 16.04 LTS | pillow | 3.1.2-0ubuntu1.6+esm4 | USN-9064-1 |
| Ubuntu Pro 14.04 LTS | pillow | 2.3.0-1ubuntu3.4+esm6 | USN-9064-1 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | python3-pillow +3 | 5.1.1-33.el8_10 | ALSA-2026:92639 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | python-pillow | 5.1.1-33.el8_10 | RLSA-2026:92639 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | python-Pillow | 7.2.0-150300.3.33.1 | SUSE-SU-2026:5038-1 |
| SLES 15 SP6 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLES 15 SP5 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLES 15 SP4 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLES 3 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 16.0 | python-Pillow | 11.3.0-160000.9.1 | SUSE-SU-2026:24656-1 |
| SLES for SAP 15 SP6 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLES for SAP 15 SP5 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLES for SAP 15 SP4 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLES 16.0 | python-Pillow | 11.3.0-160000.9.1 | SUSE-SU-2026:24656-1 |
| SLE HPC 15 SP5 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
| SLE HPC 15 SP4 | python-Pillow | 9.5.0-150400.5.28.1 | SUSE-SU-2026:5194-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python-Pillow | 13.0.0-2.1 | openSUSE-SU-2026:12251-1 |
| openSUSE Leap 16.0 | python-Pillow | 11.3.0-160000.9.1 | openSUSE-SU-2026:22246-1 |
Amazon Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Amazon Linux 2023 | python3-pillow +2 | 9.4.0-2.amzn2023.0.13 | ALAS2023-2026-3441 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | python3-pillow +3 | 5.1.1-33.el8_10 | ELSA-2026-92639 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | open-webui +1 | No fix yet | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | pillow | >= 5.1.0, < 13.0.0 | 13.0.0 | GHSA-mrfp-p49p-3hf2 |
Advisories 11
- USN-9064-1 pillow vulnerabilities Ubuntu Security Notices (USN) · Nov 13, 2026
- WID-SEC-2026-4243 Red Hat Enterprise Linux (pillow and aspell): Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 12, 2026
- SUSE-SU-2026:24656-1 Security update for python-Pillow SUSE / openSUSE Security Updates · Nov 12, 2026
- SUSE-SU-2026:5194-1 Security update for python-Pillow SUSE / openSUSE Security Updates · Nov 12, 2026
- ALAS2023-2026-3441 Important: python-pillow security update (Amazon Linux 2023) Amazon Linux Security Center (ALAS) · Nov 12, 2026
- openSUSE-SU-2026:22246-1 Security update for python-Pillow SUSE / openSUSE Security Updates · Nov 11, 2026
- SUSE-SU-2026:5038-1 Security update for python-Pillow SUSE / openSUSE Security Updates · Nov 3, 2026
- RLSA-2026:92639 Important: python-pillow security update Rocky Linux Security Advisories · Oct 30, 2026
- ALSA-2026:92639 Important: python-pillow security update AlmaLinux Security Advisories · Oct 30, 2026
- ELSA-2026-92639 Important: python-pillow security update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · Oct 30, 2026
- openSUSE-SU-2026:12251-1 python313-Pillow-13.0.0-2.1 on GA media SUSE / openSUSE Security Updates · Oct 24, 2026