CVE-2021-25290Public exploitNetwork attack vector

Service crash via negative TIFF read size

Published Mar 19, 2021 · Updated Aug 3, 2024

Buffer overflow in Pillow before 8.1.1 allows remote attackers to crash image-processing services by supplying a crafted TIFF image. _tiffReadProc in TiffDecode.c subtracts a stream location beyond the end of file, producing a negative copy length for memcpy. The application must decode attacker-supplied TIFF data; successful exploitation interrupts the processing service without reported data disclosure or modification.

CVSS severity8.7
High
EPSS probability2.37%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Buffer overflow in Pillow before 8.1.1 allows remote attackers to crash image-processing services by supplying a crafted TIFF image. _tiffReadProc in TiffDecode.c subtracts a stream location beyond the end of file, producing a negative copy length for memcpy. The application must decode attacker-supplied TIFF data; successful exploitation interrupts the processing service without reported data disclosure or modification.

The record

CVE
CVE-2021-25290
Published
Mar 19, 2021
Updated
Aug 3, 2024
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-787, T1499.004
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 19, 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 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
8.7GitHubCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N

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
T1499.004Application or System Exploitation

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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