CVE catalog
CVE-2026-102997
pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF containing a partially malformed /FlateDecode stream with padded data can force pypdf/filters.py to use ineffici
- Severity
- High · CVSS 8.7
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:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - Published
- Updated
- Source
- [NVD] · [CVE record]
- EPSS
- 0.34% · Oct 25, 2026
pypdf is a free and open-source pure-python PDF library. Prior to 6.18.1, a crafted PDF containing a partially malformed /FlateDecode stream with padded data can force pypdf/filters.py to use inefficient byte-by-byte decompression while the earlier recovery counter fails to advance for bytes that successfully decode, causing long runtimes and application unavailability. This is a residual issue after the malformed FlateDecode recovery fix. This issue is fixed in version 6.18.1.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Debian | pypdf | sid | 6.21.1-1 | fixed |
| Debian | pypdf | forky | 6.21.1-1 | fixed |
| Debian | pypdf | trixie | 5.4.0-1 | vulnerable |
| Debian | pypdf | bookworm | 3.4.1-1+deb12u1 | vulnerable |
| Debian | pypdf2 | bookworm | 2.12.1-3+deb12u1 | vulnerable |
| PyPI | pypdf | Not reported | 6.18.1 | fixed |
| Pip | pypdf | Not reported | 6.18.1 | fixed |
| Cpe | pypdf | Not reported | 6.18.1 | fixed |
Fixed-version evidence
| Distribution | Package | Type | Release | Fixed version | Urgency | Origin | Bugs |
|---|---|---|---|---|---|---|---|
| Debian | pypdf | source | sid | 6.19.0-1 | not yet assigned | Not reported | Not reported |
| Debian | pypdf | source | forky | 6.19.0-1 | not yet assigned | Not reported | Not reported |
| Debian | pypdf | source | trixie | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | pypdf | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| Debian | pypdf2 | source | bookworm | (unfixed) | not yet assigned | Not reported | Not reported |
| PyPI | pypdf | PyPI | Not reported | 6.18.1 | Not reported | PYSEC-2026-4156 | Not reported |
| Pip | pypdf | pip | Not reported | 6.18.1 | Not reported | GHSA-JW7Q-GVRG-4VJ3 | Not reported |
| Cpe | pypdf | cpe | Not reported | 6.18.1 | Not reported | NVD-CVE-2026-102997 | Not reported |
Notes
[trixie] pypdf: Minor issue [bookworm] pypdf: Minor issue, DoS [bookworm] pypdf2: Minor issue, DoS
OpenFactory catalog packages
[Debian 12 (Bookworm)]
- [python3-pypdf]Affected
Source package: [pypdf]
Details (2)
3.4.1-1+deb12u1· all · bookwormAffected
nvd · pypdf · debian · bookworm; nvd · pypdf · debian · 12
3.4.1-1+deb12u1· all · bookwormAffected
nvd · pypdf · debian · bookworm; nvd · pypdf · debian · 12
- [python3-pypdf2]Affected
Source package: [pypdf2]
Details (2)
2.12.1-3+deb12u1· all · bookwormAffected
nvd · pypdf2 · debian · bookworm; nvd · pypdf2 · debian · 12
2.12.1-3+deb12u1· all · bookwormAffected
nvd · pypdf2 · debian · bookworm; nvd · pypdf2 · debian · 12
[Debian 13 (Trixie)]
- [python3-pypdf]Affected
Source package: [pypdf]
Details (2)
5.4.0-1· all · trixieAffected
nvd · pypdf · debian · 13
5.4.0-1· all · trixieAffected
nvd · pypdf · debian · 13
Observed:
References
- [https://github.com/advisories/GHSA-jw7q-gvrg-4vj3]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-102997]
- [https://osv.dev/vulnerability/DEBIAN-CVE-2026-102997]
- [https://osv.dev/vulnerability/PYSEC-2026-4156]
- [https://security-tracker.debian.org/tracker/CVE-2026-102997]
- [https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-102997.json]
[Debian Security Tracker] · [FIRST EPSS] · [GitHub Advisory Database] · [National Vulnerability Database (NVD)] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX]