Description
pypdf is a free and open-source pure-python PDF library. Prior to 6.20.1, removing an object from a crafted cyclic PDF tree, such as an outline item, can enter an infinite loop and block the current process. This issue is fixed in version 6.20.1.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| py-pdf | pypdf | < 6.20.1 | — |
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 | pypdf | 6.21.0-1 | — |
| Debian 13 | pypdf | No fix yet | — |
| Debian 12 | pypdf +1 | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | pypdf | No fix yet | — |
| Ubuntu 26.04 LTS | pypdf | No fix yet | — |
| Ubuntu 24.04 LTS | pypdf +1 | No fix yet | — |
| Ubuntu 22.04 LTS | pypdf2 | No fix yet | — |
| Ubuntu 20.04 LTS | pypdf2 | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 18.04 LTS | pypdf2 | No fix yet | — |
| Ubuntu Pro 16.04 LTS | pypdf2 | No fix yet | — |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Leap 16.0 | python-pypdf | 6.19.0-bp160.2.1 | openSUSE-SU-2026:22188-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | open-webui | 0.12.3-r5 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| PyPI | pypdf | < 6.20.1 | 6.20.1 | GHSA-9mx8-4j7g-633p |
Advisories 1
- openSUSE-SU-2026:22188-1 Security update for python-pypdf SUSE / openSUSE Security Updates · Nov 1, 2026