CVE-2020-21678Public exploit

Converter crash via font-family out-of-bounds read

Published Aug 10, 2021 · Updated Aug 4, 2024

Global buffer overflow in fig2dev 3.2.7b allows attackers to crash the converter by transforming a crafted Xfig file to MetaPost. During MetaPost output, genmp_writefontmacro_latex reads eight bytes before the global texfontfamily array at genmp.c line 1274. Exploitation requires local conversion or user interaction with attacker-supplied input; the documented consequence is process termination.

CVSS severity5.5
Medium
EPSS probability0.66%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Global buffer overflow in fig2dev 3.2.7b allows attackers to crash the converter by transforming a crafted Xfig file to MetaPost. During MetaPost output, genmp_writefontmacro_latex reads eight bytes before the global texfontfamily array at genmp.c line 1274. Exploitation requires local conversion or user interaction with attacker-supplied input; the documented consequence is process termination.

The record

CVE
CVE-2020-21678
Published
Aug 10, 2021
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-120, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 10, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record 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 vectorlocal
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
4.3NIST NVDAV:N/AC:M/Au:N/C:N/I:N/A:P

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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-120Buffer Copy without Checking Size of Input ('Classic Buffer Overflow')
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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