CVE-2026-84309 | BDVDB-2026-367163 Detail

py-pdfpypdf

Description#

pypdf is a free and open-source pure-python PDF library. Prior to 6.16.0, an attacker can craft a PDF whose cyclic tree structure causes pypdf/generic/_data_structures.py TreeObject.insert_child to follow /Next links indefinitely when a writing code path inserts a child, producing an infinite loop. This issue is fixed in version 6.16.0.

Impact#

Per CVSS v4.0: confidentiality impact none, integrity impact none, availability impact high. Attack vector: local.

Weaknesses#

CWE-835 Loop with Unreachable Exit Condition ('Infinite Loop')

References#

Exploit#

No public exploit known

History#

Version 12026-09-01Record published in the CVE List.
Version 22026-09-02Most recent update recorded in the CVE List.

Published

Published: 2026-09-01
Last modified: 2026-09-02

Vendor information

Vendor: py-pdf
Product: pypdf

All py-pdf vulnerabilities

Score

6.9 Medium

EPSS

less than 1%, Very Low

Estimated chance of exploitation in the next 30 days. EPSS percentile: 8.3.

KEV

Not listed in the CISA Known Exploited Vulnerabilities catalog.

Impact

Not classified

Action

No specific action is recorded in the source data. Check the references for vendor guidance.

Affected Systems

Vulnerable
< 6.16.0
Fixed
Not stated

Scoring System

CVSS v4.0

6.9 Medium

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

Metric breakdown
Attack Vector	Local
Attack Complexity	Low
Attack Requirements	None
Privileges Required	None
User Interaction	None
Vulnerable System Confidentiality	None
Vulnerable System Integrity	None
Vulnerable System Availability	High
Subsequent System Confidentiality	None
Subsequent System Integrity	None
Subsequent System Availability	None

CVSS v3.1

Not available

CVSS v3.0

Not available

CVSS v2

Not available

Source: CVE List v5 (record); CISA KEV (kev, action); FIRST EPSS (epss).