Code execution via FontParser heap buffer overflow
Published Jun 9, 2020 · Updated Aug 4, 2024
Out-of-bounds write in FontParser in affected Apple operating systems allows attackers to execute code through a crafted PDF file. TParsingContext::Subroutine passes the encrypted-buffer length instead of the resized length to LenIVDecrypt, writing beyond an allocated heap buffer. Exploitation requires a user to visit a malicious page or open the file and yields code execution in the current process or an application crash.
Summary
What happened
Out-of-bounds write in FontParser in affected Apple operating systems allows attackers to execute code through a crafted PDF file. TParsingContext::Subroutine passes the encrypted-buffer length instead of the resized length to LenIVDecrypt, writing beyond an allocated heap buffer. Exploitation requires a user to visit a malicious page or open the file and yields code execution in the current process or an application crash.
The record
- CVE
- CVE-2020-9816
- Published
- Jun 9, 2020
- Updated
- Aug 4, 2024
- Vendor
- Apple
- Product
- iOS
- Classifications
- CWE-787, T1203
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 9, 2020CVE publishedPublication date reported by the CVE source.
- Aug 4, 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.
- Affected versionversion=unspecified <iOS 13.5 and iPadOS 13.5
What conditions does exploitation require?
What is affected?
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.
Public exploit references
- STAR Labs evil_font and evil_pdf.pdf proof of conceptproof of concept · demonstrated
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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