Application crash via unchecked Unix socket path
Published Jun 17, 2020 · Updated Aug 5, 2024
Buffer overflow in LibVNCServer before 0.9.13 allows remote attackers to crash applications via a long Unix socket filename. ConnectClientToUnixSock() copies the caller-supplied path into sockaddr_un.sun_path with strcpy without first checking the destination size. Exploitation requires an application to call that function directly with an oversized name; common ConnectToRFBServer() use rejects it, and compiled-in overflow checks limit the result to a crash.
Summary
What happened
Buffer overflow in LibVNCServer before 0.9.13 allows remote attackers to crash applications via a long Unix socket filename. ConnectClientToUnixSock() copies the caller-supplied path into sockaddr_un.sun_path with strcpy without first checking the destination size. Exploitation requires an application to call that function directly with an oversized name; common ConnectToRFBServer() use rejects it, and compiled-in overflow checks limit the result to a crash.
The record
- CVE
- CVE-2019-20839
- Published
- Jun 17, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-120, T1499
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Jun 17, 2020CVE publishedPublication date reported by the CVE source.
- Aug 5, 2024Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What is affected?
Affected products and versions are unavailable in this record.
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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