CVE-2021-29463

Denial of service via WebP metadata bounds read

Published Apr 30, 2021 · Updated Oct 15, 2024

Out-of-bounds read in Exiv2 before 0.27.4 allows attackers to crash Exiv2 via a crafted WebP image when metadata is written. Exiv2::WebPImage::doWriteMetadata reads beyond the WebP buffer while performing metadata insertion, producing a process crash. The attacker must supply the crafted image and cause Exiv2 to execute a write operation such as insert; ordinary metadata reads do not trigger this path.

CVSS severity5.5
Medium
EPSS probability1.12%
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 read in Exiv2 before 0.27.4 allows attackers to crash Exiv2 via a crafted WebP image when metadata is written. Exiv2::WebPImage::doWriteMetadata reads beyond the WebP buffer while performing metadata insertion, producing a process crash. The attacker must supply the crafted image and cause Exiv2 to execute a write operation such as insert; ordinary metadata reads do not trigger this path.

The record

CVE
CVE-2021-29463
Published
Apr 30, 2021
Updated
Oct 15, 2024
Vendor
Exiv2
Product
Exiv2
Classifications
CWE-125, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 30, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 15, 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?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=< 0.27.4

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Exiv2 · Exiv2version=< 0.27.4

Published CVSS scores

4.3NVDAV:N/AC:M/Au:N/C:N/I:N/A:P
3.3GitHubCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
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 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-125Out-of-bounds Read
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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