CVE-2026-84310

Denial of service via unbounded outline traversal

Published Sep 1, 2026 · Updated Sep 1, 2026

Uncontrolled resource consumption in pypdf before 6.16.1 allows context-dependent attackers to exhaust resources via crafted PDFs. The _get_outline traversal follows numerous entries and deeply nested reused paths without global entry-count or nesting-depth limits. Exploitation requires an application to retrieve outlines from an attacker-supplied PDF, resulting in processing delays or memory-exhaustion service interruption.

CVSS severityUnavailable
Unscored
EPSS probability0.14%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Uncontrolled resource consumption in pypdf before 6.16.1 allows context-dependent attackers to exhaust resources via crafted PDFs. The _get_outline traversal follows numerous entries and deeply nested reused paths without global entry-count or nesting-depth limits. Exploitation requires an application to retrieve outlines from an attacker-supplied PDF, resulting in processing delays or memory-exhaustion service interruption.

The record

CVE
CVE-2026-84310
Published
Sep 1, 2026
Updated
Sep 1, 2026
Vendor
py-pdf
Product
pypdf
Classifications
T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Sep 1, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 6.16.1

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

py-pdf · pypdfversion=< 6.16.1

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

T1499.004Application or System Exploitation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo