CVE-2020-36023Public exploitNetwork attack vector

Application hang via malformed Type 1C glyph

Published Aug 11, 2023 · Updated Nov 3, 2025

Denial of service in Poppler 20.12.1 allows remote attackers to hang a PDF-processing application through a crafted PDF file. The FoFiType1C::cvtGlyph function enters a loop with an unreachable exit condition while converting malformed Type 1C glyph data. Exploitation requires a user or automated system to open the file, and the resulting hang interrupts the processing application.

CVSS severity6.5
Medium
EPSS probability1.17%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Denial of service in Poppler 20.12.1 allows remote attackers to hang a PDF-processing application through a crafted PDF file. The FoFiType1C::cvtGlyph function enters a loop with an unreachable exit condition while converting malformed Type 1C glyph data. Exploitation requires a user or automated system to open the file, and the resulting hang interrupts the processing application.

The record

CVE
CVE-2020-36023
Published
Aug 11, 2023
Updated
Nov 3, 2025
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-835, T1499, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 11, 2023CVE publishedPublication date reported by the CVE source.
  2. Nov 3, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

6.5CanonicalCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
6.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

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.

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No observations available

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

Weakness, pattern, technique

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
T1499Endpoint Denial of Service
T1204.002Malicious File

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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