GHSA-x7hp-r3qg-r3cj

pypdf: Manipulated FlateDecode XFA streams can exhaust RAM

Source: GitHub Advisory Database (reviewed) Moderate CVE-2026-27888

Packages

Ecosystem	Package	Affected	Fixed in
PyPI	pypdf	< 6.7.3	6.7.3

Details

As written in the advisory (Markdown source, shown as plain text).

### Impact An attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires accessing the `xfa` property of a reader or writer and the corresponding stream being compressed using `/FlateDecode`. ### Patches This has been fixed in [pypdf==6.7.3](https://github.com/py-pdf/pypdf/releases/tag/6.7.3). ### Workarounds If projects cannot upgrade yet, consider applying the changes from PR [#3658](https://github.com/py-pdf/pypdf/pull/3658).

References

External links from the advisory. They lead to third-party sites.

https://github.com/py-pdf/pypdf/security/advisories/GHSA-x7hp-r3qg-r3cj web
https://nvd.nist.gov/vuln/detail/CVE-2026-27888 advisory
https://github.com/py-pdf/pypdf/pull/3658 web
https://github.com/py-pdf/pypdf/commit/7a4c8246ed48d9d328fb596942271da47b6d109c web
https://github.com/py-pdf/pypdf package
https://github.com/py-pdf/pypdf/releases/tag/6.7.3 web