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Vulnerabilities

Vulnerability · CVE-2026-119205

pypdf has possible infinite loop when cloning dictionaries

Published Oct 30, 2026 · catalog updated Oct 30, 2026 · pypdf has possible infinite

Last checked Nov 6, 2026. A connected source was read within the last 7 days.

Check if you run it

No confirmed exploitation is on record for CVE-2026-119205. EPSS is 0.22%. Act only if a listed version of pypdf has possible infinite is installed.

Gaps on this record

  • The stored product name is a package slug. The name on this page is taken from the title (pypdf has possible infinite).
  • No vendor fix or required action is stored. Compare the linked advisory before you change production.
Severity
High—
Known exploitation
Not in CISA/VulnCheck KEV
EPSS
0.22%
Remediation
Version ranges on file
Affected products
PyPI pypdf · pip pypdf · pypi pypdf

An attacker who uses this vulnerability can craft a PDF which leads + to an infinite loop. This requires cloning/duplicating a ." +date: "2026-10-30" +pubdate: "2026-10-30" +affected_range: "<6.21.4" +fixed_versions: +- "6.21.4" +affected_versions: "All versions before 6.21.4" +not_impacted: "All versions starting from 6.21.4" +solution: "Upgrade to version 6.21.4 or above." +urls: +- "https://nvd

Are you affected?

Enter the version you run. The result uses only the ranges stored on this record.

The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.

  • PyPI pypdf0 → 6.21.4
  • pip pypdf< 6.21.4
  • pypi pypdf<6.21.4

How to fix CVE-2026-119205

What to do

Three questions, each answered from this record only. Confirm the vendor advisory before you patch.

Should you patch?

No confirmed exploitation is on record for CVE-2026-119205. EPSS is 0.22%. Act only if a listed version of pypdf has possible infinite is installed.

Which versions are affected?

Compare what you have installed with 0 → 6.21.4, < 6.21.4, <6.21.4. Compare the installed version with the linked vendor advisory before you change production.

What should an analyst verify?

CWE-835: Infinite Loop. EPSS 0.22%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.

Code

The project this record applies to. Exploit listings stay in References.

Timeline

Detection, updates, and resolution for this record.

  1. Oct 30, 2026 · GitHub Advisory Database

    Detected

    ### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires cloning/duplicating a . ### Patches This has been fixed in [pypdf==6.21.4](https://github.com/py-pdf/pypdf/releases/tag/6.21.4). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#4288](https://github.com/py-pdf/pypdf/pull/4288).

  2. Oct 30, 2026 · GitHub Advisory Database

    Fix available

    pypdf fixed in 6.21.4

  3. Oct 30, 2026 · GitHub Advisory Database

    Fix available

    pypdf fixed in 6.21.4

  4. Oct 30, 2026 · GitHub Advisory Database

    Updated

    ### Impact An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires cloning/duplicating a . ### Patches This has been fixed in [pypdf==6.21.4](https://github.com/py-pdf/pypdf/releases/tag/6.21.4). ### Workarounds If you cannot upgrade yet, consider applying the changes from PR [#4288](https://github.com/py-pdf/pypdf/pull/4288).

Sources

  • CVE.orgVulnerability recordCVE-2026-119205

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-119205

    30-day exploitation probability 0.22%

    first.org
  • GitHub Advisory DatabasePackage advisoryGHSA-mfr5-77xh-9j7h

    pypdf has possible infinite loop when cloning dictionaries

    github.com
  • GitLab Advisory DatabasePackage advisoryCVE-2026-119205

    An attacker who uses this vulnerability can craft a PDF which leads to an infinite loop. This requires cloning/duplicating a DictionaryObject.

    advisories.gitlab.com
  • GitLab Advisory DatabasePackage advisorypypi/pypdf/CVE-2026-119205.yml

    An attacker who uses this vulnerability can craft a PDF which leads + to an infinite loop. This requires cloning/duplicating a ." +date: "2026-10-30" +pubdate: "2026-10-30" +affected_range: "<6.21.4" +fixed_versions: +- "6.21.4" +affected_versions: "All versions before 6.21.4" +not_impacted: "All versions starting from 6.21.4" +solution: "Upgrade to version 6.21.4 or above." +urls: +- "https://nvd

    gitlab.com
  • OpenSSF OSV / OSV ScannerPackage advisoryGHSA-mfr5-77xh-9j7h

    pypdf has possible infinite loop when cloning dictionaries

    osv.dev
  • PyPA Advisory DatabasePackage advisoryGHSA-mfr5-77xh-9j7h

    pypdf has possible infinite loop when cloning dictionaries

    osv.dev

References

Freshness

Last verified in this catalog Nov 6, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.

  • FIRST EPSSNov 6, 2026
  • GitHub Advisory DatabaseNov 6, 2026
  • GitLab Advisory DatabaseNov 3, 2026
  • PyPA Advisory DatabaseNov 2, 2026
  • GitLab Advisory DatabaseNov 1, 2026
  • CVE.orgOct 31, 2026
  • OpenSSF OSV / OSV ScannerOct 31, 2026