CVE-2021-40263Public exploitNetwork attack vector

Code execution via mismatched TIFF tile dimensions

Published Aug 22, 2023 · Updated Oct 3, 2024

Heap overflow in FreeImage 1.18.0 allows context-dependent attackers to corrupt memory by supplying a crafted tiled TIFF image. PluginTIFF.cpp allocates the destination bitmap from ImageWidth but uses attacker-controlled TileWidth-derived row sizes in memcpy operations. A host application must process the file; the demonstrated result is an access-violation crash, while successful memory corruption can execute code in that process.

CVSS severity8.8
High
EPSS probability1.16%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Heap overflow in FreeImage 1.18.0 allows context-dependent attackers to corrupt memory by supplying a crafted tiled TIFF image. PluginTIFF.cpp allocates the destination bitmap from ImageWidth but uses attacker-controlled TileWidth-derived row sizes in memcpy operations. A host application must process the file; the demonstrated result is an access-violation crash, while successful memory corruption can execute code in that process.

The record

CVE
CVE-2021-40263
Published
Aug 22, 2023
Updated
Oct 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 22, 2023CVE publishedPublication date reported by the CVE source.
  2. Oct 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 vectornetwork
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/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 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

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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