CVE-2026-22690Public exploit

Processing slowdown via unbounded Root object recovery

Published Jan 10, 2026 · Updated Jan 10, 2026

Uncontrolled resource consumption in pypdf before 6.6.0 allows attackers to delay PDF processing through a malformed document. In non-strict mode, PdfReader.root_object trusts the trailer's /Size value and calls get_object for every candidate when /Root is absent, without a recovery limit. Attackers must cause an application to parse the crafted PDF; the resulting object scan consumes processing time but does not expose or alter data.

CVSS severity5.3
Medium
EPSS probability0.44%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Uncontrolled resource consumption in pypdf before 6.6.0 allows attackers to delay PDF processing through a malformed document. In non-strict mode, PdfReader.root_object trusts the trailer's /Size value and calls get_object for every candidate when /Root is absent, without a recovery limit. Attackers must cause an application to parse the crafted PDF; the resulting object scan consumes processing time but does not expose or alter data.

The record

CVE
CVE-2026-22690
Published
Jan 10, 2026
Updated
Jan 10, 2026
Vendor
py-pdf
Product
pypdf
Classifications
CWE-400, T1499.004
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Jan 10, 2026CVE publishedPublication date reported by the CVE source.
  2. Jan 10, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=< 6.6.0

What conditions does exploitation require?

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

What is affected?

py-pdf · pypdfversion=< 6.6.0

Published CVSS scores

2.7GitHub, Inc.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/E:U
5.3NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-400Uncontrolled Resource Consumption
T1499.004Application or System Exploitation

Public exploit references

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

Technologies

Your stack

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Your stack

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