Code execution via malformed PDB integer underflow
Published Sep 12, 2023 · Updated Oct 30, 2025
Integer underflow in DiaSymReader in Microsoft .NET and Visual Studio allows attackers to execute code via a crafted PDB file. Microsoft disclosed that Microsoft.DiaSymReader.Native.amd64.dll underflows an integer while reading a corrupted PDB, but did not identify the affected calculation. Execution requires user interaction with content that causes the Windows reader to process the file; successful exploitation runs attacker-controlled code.
Summary
What happened
Integer underflow in DiaSymReader in Microsoft .NET and Visual Studio allows attackers to execute code via a crafted PDB file. Microsoft disclosed that Microsoft.DiaSymReader.Native.amd64.dll underflows an integer while reading a corrupted PDB, but did not identify the affected calculation. Execution requires user interaction with content that causes the Windows reader to process the file; successful exploitation runs attacker-controlled code.
The record
- CVE
- CVE-2023-36796
- Published
- Sep 12, 2023
- Updated
- Oct 30, 2025
- Vendor
- Microsoft
- Product
- Microsoft .NET Framework 3.5 and 4.8.1
- Classifications
- CWE-191, T1204.002
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 12, 2023CVE publishedPublication date reported by the CVE source.
- Oct 30, 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=4.8.1 <4.8.09186.01
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.
Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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