VulnerabilityAnalyzed

CVE-2026-102998

pypdf is a free and open-source pure-python PDF library.

HIGH 8.7EPSS 0.34%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.34%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

pypdf is a free and open-source pure-python PDF library. Prior to 6.19.0, a crafted PDF with form field values can cause pypdf/generic/_appearance_stream.py appearance-stream generation to repeat invariant selection-data work inside a loop when an application updates fields with flattening enabled, resulting in excessive runtimes and application unavailability. This issue is fixed in version 6.19.0.

CVSS 4.0: 8.7 HIGHCVSS: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/M
EPSS: 0.34% probability · 27th percentile
Public exploits: None in Exploit-DB
CISA KEV: Not listed
Weakness: CWE-400
Affected: pypdf project/pypdf
Source: security-advisories@github.com

EPSS trend

EPSS moved from 0.5% on 1 October 2026 to 0.3% on 26 October 2026.

References

https://github.com/py-pdf/pypdf/commit/959467a9b95be83e2dc5ae873ece5f371263ede7Patch
https://github.com/py-pdf/pypdf/pull/4087Patch, Issue Tracking
https://github.com/py-pdf/pypdf/releases/tag/6.19.0Release Notes
https://github.com/py-pdf/pypdf/security/advisories/GHSA-php9-fj8v-98fjVendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.