CVE-2021-27224Public exploitNetwork attack vector

Code execution via unchecked WPG buffer write

Published Feb 17, 2021 · Updated Aug 3, 2024

Out-of-bounds write in the WPG.dll plugin for IrfanView 4.57 allows remote attackers to execute code through a crafted WPG file. The WPG parser computes destination addresses from file-derived state and writes decoded bytes in sub_7C42E78 without keeping the pointer within the allocated image buffer. Exploitation requires a user to open the malicious image; the demonstrated immediate consequence is an application crash, while the non-null write is classified as exploitable.

CVSS severity7.5
High
EPSS probability37.99%
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 the WPG.dll plugin for IrfanView 4.57 allows remote attackers to execute code through a crafted WPG file. The WPG parser computes destination addresses from file-derived state and writes decoded bytes in sub_7C42E78 without keeping the pointer within the allocated image buffer. Exploitation requires a user to open the malicious image; the demonstrated immediate consequence is an application crash, while the non-null write is classified as exploitable.

The record

CVE
CVE-2021-27224
Published
Feb 17, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1203, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Feb 17, 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

Compare your product and version with the public record. A matching version still requires validation against your environment.

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

7.5NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
5.0NIST NVDAV:N/AC:L/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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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-787Out-of-bounds Write
T1203Exploitation for Client Execution
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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