CVE-2021-21103Network attack vector

Memory disclosure via CGM out-of-bounds read

Published Sep 8, 2021 · Updated Sep 17, 2024

Memory corruption in Adobe Illustrator 25.2 and earlier allows remote attackers to disclose memory through a crafted CGM file. The Reader_for_CGM plugin fails to bounds-check malformed CGM data and reads beyond the intended buffer. Exploitation requires a user to open the file, and the disclosed data comes from the Illustrator process running in the current user's context.

CVSS severity4.3
Medium
EPSS probability3.28%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Memory corruption in Adobe Illustrator 25.2 and earlier allows remote attackers to disclose memory through a crafted CGM file. The Reader_for_CGM plugin fails to bounds-check malformed CGM data and reads beyond the intended buffer. Exploitation requires a user to open the file, and the disclosed data comes from the Illustrator process running in the current user's context.

The record

CVE
CVE-2021-21103
Published
Sep 8, 2021
Updated
Sep 17, 2024
Vendor
Adobe
Product
Illustrator
Classifications
CWE-787, CWE-788, T1204.002
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Sep 8, 2021CVE publishedPublication date reported by the CVE source.
  2. Sep 17, 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=unspecified <=25.2
  2. Affected versionversion=unspecified <=None

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

Adobe · Illustratorversion=unspecified <=25.2; version=unspecified <=None

Published CVSS scores

4.3Adobe Systems IncorporatedCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
9.3NIST NVDAV:N/AC:M/Au:N/C:C/I:C/A:C
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.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

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 exploitUnconfirmed

Weakness, pattern, technique

CWE-787Out-of-bounds Write
CWE-788Access of Memory Location After End of Buffer
T1204.002Malicious File

Public exploit references

No public exploit references are available in this record.

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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