CVE-2021-21773Public exploit

Memory corruption via undersized TIFF I/O buffer

Published Mar 31, 2021 · Updated Aug 3, 2024

Out-of-bounds write in Accusoft ImageGear 19.8 allows attackers to corrupt memory by supplying a crafted TIFF file. The tiff_read_sub_1 path accepts a one-byte allocation after failing to reject a null size field, then init_io_buffer writes structure fields beyond that heap buffer. A host application must load the file; the resulting corruption can crash the process or execute code in the process context.

CVSS severity8.1
High
EPSS probability0.68%
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 Accusoft ImageGear 19.8 allows attackers to corrupt memory by supplying a crafted TIFF file. The tiff_read_sub_1 path accepts a one-byte allocation after failing to reject a null size field, then init_io_buffer writes structure fields beyond that heap buffer. A host application must load the file; the resulting corruption can crash the process or execute code in the process context.

The record

CVE
CVE-2021-21773
Published
Mar 31, 2021
Updated
Aug 3, 2024
Vendor
Accusoft
Product
ImageGear
Classifications
CWE-754, CWE-131, T1203
Attack vector
local
Privileges
unauthenticated

Timeline

How it unfolded

  1. Mar 31, 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?

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

  1. Affected versionversion=Accusoft ImageGear 19.8

What conditions does exploitation require?

Attack vectorlocal
Required privilegesunauthenticated

What is affected?

Accusoft · ImageGearversion=Accusoft ImageGear 19.8

Published CVSS scores

6.8NIST NVDAV:N/AC:M/Au:N/C:P/I:P/A:P
8.1Cisco TalosCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
7.8NIST NVDCVSS:3.1/AV:L/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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-754Improper Check for Unusual or Exceptional Conditions
CWE-131Incorrect Calculation of Buffer Size
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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