Identity confusion and host crash via POSIX race
Published Jul 8, 2026 · Updated Jul 8, 2026
Race condition in CoreWCF UnixDomainSocket before 1.8.1 and in 1.9.0 allows local users to misattribute peers or crash the host. UnixDomainSocketInterop calls non-reentrant getpwuid and getgrgid, whose pointers reference shared libc buffers that concurrent lookups overwrite before managed marshalling copies them. Exploitation requires concurrent access to a locally reachable Unix domain socket; it can assign another connection’s identity or terminate the service process.
Summary
What happened
Race condition in CoreWCF UnixDomainSocket before 1.8.1 and in 1.9.0 allows local users to misattribute peers or crash the host. UnixDomainSocketInterop calls non-reentrant getpwuid and getgrgid, whose pointers reference shared libc buffers that concurrent lookups overwrite before managed marshalling copies them. Exploitation requires concurrent access to a locally reachable Unix domain socket; it can assign another connection’s identity or terminate the service process.
The record
- CVE
- CVE-2026-54778
- Published
- Jul 8, 2026
- Updated
- Jul 8, 2026
- Vendor
- CoreWCF
- Product
- CoreWCF
- Classifications
- CWE-825, CWE-362, T1499.004
- Attack vector
- local
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jul 8, 2026CVE publishedPublication date reported by the CVE source.
- Jul 8, 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=< 1.8.1
- Affected versionversion=>= 1.9.0, < 1.9.1
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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