Overview
About vulnerability
Impact
An attacker who uses this vulnerability can craft a PDF which leads to large memory usage. This requires parsing a content stream with a rather large /Length value, regardless of the actual data length inside the stream.
Patches
This has been fixed in [pypdf==6.8.0](https://github.com/py-pdf/pypdf/releases/tag/6.8.0).
Workarounds
If you cannot upgrade yet, consider applying the changes from PR [#3675](https://github.com/py-pdf/pypdf/pull/3675).
As far as we are aware, this mostly affects reading from buffers of unknown size, as returned by open("file.pdf", mode="rb") for example. Passing a file path or a BytesIO buffer to pypdf instead does not seem to trigger the vulnerability.
Details
- Affected product:
- pypdf
- Affected packages:
- pypdf @ 5.9.0