CVE-2021-29366Public exploit

Arbitrary code execution via malformed RLE parsing

Published Sep 28, 2021 · Updated Aug 3, 2024

Out-of-bounds write in IrfanView 4.57 allows context-dependent attackers to execute arbitrary code via a crafted RLE file. The FORMATS plug-in's GetPlugInInfo routine writes beyond its intended buffer while extracting information from attacker-controlled RLE data. Exploitation requires a user to open the file, after which code runs with the privileges of the IrfanView process.

CVSS severity7.8
High
EPSS probability0.98%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Out-of-bounds write in IrfanView 4.57 allows context-dependent attackers to execute arbitrary code via a crafted RLE file. The FORMATS plug-in's GetPlugInInfo routine writes beyond its intended buffer while extracting information from attacker-controlled RLE data. Exploitation requires a user to open the file, after which code runs with the privileges of the IrfanView process.

The record

CVE
CVE-2021-29366
Published
Sep 28, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1203, T1204.002
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 28, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 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

7.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
6.8NIST NVDAV: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)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-787Out-of-bounds Write
T1203Exploitation for Client Execution
T1204.002User Execution: Malicious 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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