CVE-2021-27815Public exploit

Application crash via empty EXIF XML value

Published Apr 14, 2021 · Updated Aug 3, 2024

NULL pointer dereference in libexif exif 0.6.22 and earlier allows context-dependent attackers to crash the application via a crafted JPEG. The escape_xml function skips its allocation loop for an empty EXIF text value, then writes a terminator through the still-null output pointer during XML formatting. Exploitation requires the crafted file to be processed with XML output enabled and terminates only the invoked exif process.

CVSS severity5.5
Medium
EPSS probability1.27%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

NULL pointer dereference in libexif exif 0.6.22 and earlier allows context-dependent attackers to crash the application via a crafted JPEG. The escape_xml function skips its allocation loop for an empty EXIF text value, then writes a terminator through the still-null output pointer during XML formatting. Exploitation requires the crafted file to be processed with XML output enabled and terminates only the invoked exif process.

The record

CVE
CVE-2021-27815
Published
Apr 14, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-476
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Apr 14, 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

5.5NIST NVDCVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
4.3NIST NVDAV:N/AC:M/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.

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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 exploitPublished

Weakness, pattern, technique

CWE-476NULL Pointer Dereference

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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