CVE-2020-24221Public exploit

Application hang via endless GIF byte reads

Published Aug 11, 2023 · Updated Oct 9, 2024

Infinite loop in GetByte in miniupnp ngiflib 0.4 allows local users to hang GIF-processing applications via a crafted GIF file. During gif2tga parsing, GetByte repeatedly reaches the standard I/O byte-read path without an exit, so the malformed stream never completes processing. A local application must process the file; the affected process then remains unresponsive until terminated.

CVSS severity5.5
Medium
EPSS probability0.32%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Infinite loop in GetByte in miniupnp ngiflib 0.4 allows local users to hang GIF-processing applications via a crafted GIF file. During gif2tga parsing, GetByte repeatedly reaches the standard I/O byte-read path without an exit, so the malformed stream never completes processing. A local application must process the file; the affected process then remains unresponsive until terminated.

The record

CVE
CVE-2020-24221
Published
Aug 11, 2023
Updated
Oct 9, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-835, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 11, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 9, 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

5.5NVDCVSS:3.1/AV:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-835Loop with Unreachable Exit Condition ('Infinite Loop')
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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