CVE-2026-28804 MEDIUM

CVE-2026-28804: pypdf: Inefficient decoding of ASCIIHexDecode streams

Vendor Py-Pdf
Product pypdf
Weakness CWE-407
Published March 6, 2026
Last update March 6, 2026
View on NVD All CVEs

CVSS base score

6.9/10
Attack vector Network
Attack complexity Low
Privileges required None
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N

What the vulnerability does

01Description

pypdf is a free and open-source pure-python PDF library. Prior to version 6.7.5, an attacker who uses this vulnerability can craft a PDF which leads to long runtimes. This requires accessing a stream which uses the /ASCIIHexDecode filter. This issue has been patched in version 6.7.5.

Key dates

02Disclosure timeline

March 6, 2026 CVE published
March 6, 2026 Record updated