Remote code execution via unchecked COFF relocation
Published Sep 8, 2026 · Updated Sep 10, 2026
Heap-based buffer overflow in Visual Studio 2026 before 18.9.3 allows remote attackers to execute code via a crafted PDB file. DiaSymReader.Native applies an unchecked COFF relocation while parsing the PDB, causing a four-byte write beyond its heap buffer. Exploitation requires the affected application to process the attacker-supplied file and executes code in the application user's context.
Summary
What happened
Heap-based buffer overflow in Visual Studio 2026 before 18.9.3 allows remote attackers to execute code via a crafted PDB file. DiaSymReader.Native applies an unchecked COFF relocation while parsing the PDB, causing a four-byte write beyond its heap buffer. Exploitation requires the affected application to process the attacker-supplied file and executes code in the application user's context.
The record
- CVE
- CVE-2026-77907
- Published
- Sep 8, 2026
- Updated
- Sep 10, 2026
- Vendor
- Microsoft
- Product
- Microsoft Visual Studio 2026 version 18.9
- Classifications
- CWE-122, T1204.002
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Sep 8, 2026CVE publishedPublication date reported by the CVE source.
- Sep 10, 2026Record 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=18.9.0 <18.9.3
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
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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