CVE-2020-5395Network attack vector

Application crash via crafted LayerCount metadata

Published Jan 3, 2020 · Updated Aug 4, 2024

FontForge 20190801 use-after-free in SFD_GetFontMetaData allows remote attackers to crash the application via a crafted SFD font file. SFD_GetFontMetaData writes an attacker-controlled LayerCount value into the font structure before reallocating and initializing layer storage, leaving stale memory references that are later accessed. Exploitation requires user interaction to open the malicious SFD file; the demonstrated consequence is process crash, with memory-corruption impact bounded to the FontForge process.

CVSS severity8.8
High
EPSS probability2.48%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

FontForge 20190801 use-after-free in SFD_GetFontMetaData allows remote attackers to crash the application via a crafted SFD font file. SFD_GetFontMetaData writes an attacker-controlled LayerCount value into the font structure before reallocating and initializing layer storage, leaving stale memory references that are later accessed. Exploitation requires user interaction to open the malicious SFD file; the demonstrated consequence is process crash, with memory-corruption impact bounded to the FontForge process.

The record

CVE
CVE-2020-5395
Published
Jan 3, 2020
Updated
Aug 4, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-416, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jan 3, 2020CVE 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NVDAV:N/AC:M/Au:N/C:P/I:P/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-416Use After Free
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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