Code execution via unchecked TTF glyph offsets
Published Sep 13, 2023 · Updated Oct 21, 2025
Out-of-bounds write in Adobe Acrobat Reader 23.003.20284 and earlier allows attackers to execute code when a user opens a malicious PDF. The libCoolType sfac_GetSbitBitmap function merges glyph bitmaps from an embedded malformed TrueType font without checking X and Y offsets against the allocated bitmap buffer. Opening the file is required, and exploitation runs arbitrary code in the current user's context.
Summary
What happened
Out-of-bounds write in Adobe Acrobat Reader 23.003.20284 and earlier allows attackers to execute code when a user opens a malicious PDF. The libCoolType sfac_GetSbitBitmap function merges glyph bitmaps from an embedded malformed TrueType font without checking X and Y offsets against the allocated bitmap buffer. Opening the file is required, and exploitation runs arbitrary code in the current user's context.
The record
- CVE
- CVE-2023-26369
- Published
- Sep 13, 2023
- Updated
- Oct 21, 2025
- Vendor
- Adobe
- Product
- Adobe Acrobat Reader
- Classifications
- CWE-787, T1204.002, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 13, 2023CVE publishedPublication date reported by the CVE source.
- Oct 21, 2025Record 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.
- Affected versionversion=0 <=20.005.30514
What conditions does exploitation require?
What is affected?
Published CVSS scores
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.
Weakness, pattern, technique
Public exploit references
- Google Project Zero malformed TTF proof of conceptproof of concept · demonstrated
Labels summarize the accepted research assessment. They do not indicate a test against your environment.
Reported exploitation
- Adobe-reported limited in-the-wild attacksreported exploitation
- North Korean actor exploit chain against security researchersexploit chain
- CISA Known Exploited Vulnerabilities catalog entryknown exploited catalog
Technologies
Your stack
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Your stack
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