CVE-2025-55197: py-pdf pypdf · Uncontrolled Resource Consumption
Affects py-pdf pypdfSource CVE Database V5
Not known to be exploited · CVSS 6.6 Medium : upgrade to 6.0.0 when convenient.
Data as of 26 Oct 2026, 06:26 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 40% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 6.0.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:UExploitation evidence
Disclosed: evidence found.
CVE published 13 Aug 2025
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 2026-10-26.
What to do
Upgrade py-pdf pypdf to 6.0.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| py-pdf pypdf | Affected
| Fixed in
|
AI-suggested
Upgrade to pypdf version 6.0.0 or later, where this vulnerability is fixed. If upgrading is not immediately possible, implement the documented workaround for the decompression filter in pypdf.filters.decompress as described in the project's source code. No other mitigation is specified.
Description
### Impact An attacker who uses this vulnerability can craft a PDF which leads to the RAM being exhausted. This requires just reading the file if a series of FlateDecode filters is used on a malicious cross-reference stream. Other content streams are affected on explicit access. ### Patches This has been fixed in [pypdf==6.0.0](https://github.com/py-pdf/pypdf/releases/tag/6.0.0). ### Workarounds If you cannot upgrade yet, you might want to implement the workaround for `pypdf.filters.decompress` yourself: https://github.com/py-pdf/pypdf/blob/0dd57738bbdcdb63f0fb43d8a6b3d222b6946595/pypdf/filters.py#L72-L143 ### References This issue has been reported in #3429 and fixed in #3430.
References
- github.com/py-pdf/pypdf/security/advisories/GHSA-7hfw-26vp-jp8m (opens in a new tab)
- github.com/py-pdf/pypdf/issues/3429 (opens in a new tab)
- github.com/py-pdf/pypdf/pull/3430 (opens in a new tab)
- github.com/py-pdf/pypdf/blob/0dd57738bbdcdb63f0fb43d8a6b3d222b6946595/pypdf/filters.py (opens in a new tab)
- github.com/py-pdf/pypdf/releases/tag/6.0.0 (opens in a new tab)