Unauthenticated information disclosure via repeater buffer leak
Published Jun 17, 2020 · Updated Aug 5, 2024
Information disclosure in LibVNCServer before 0.9.13 allows remote attackers to read uninitialized client memory via ConnectToRFBRepeater. The libvncclient/rfbproto.c function formats a repeater host string into a fixed buffer but transmits the entire buffer, including bytes that were never initialized. An attacker controlling or receiving the repeater connection can obtain residual process-memory contents without authentication; the demonstrated impact is confidentiality loss without integrity or availability effects.
Summary
What happened
Information disclosure in LibVNCServer before 0.9.13 allows remote attackers to read uninitialized client memory via ConnectToRFBRepeater. The libvncclient/rfbproto.c function formats a repeater host string into a fixed buffer but transmits the entire buffer, including bytes that were never initialized. An attacker controlling or receiving the repeater connection can obtain residual process-memory contents without authentication; the demonstrated impact is confidentiality loss without integrity or availability effects.
The record
- CVE
- CVE-2018-21247
- Published
- Jun 17, 2020
- Updated
- Aug 5, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-200
- 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
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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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Public exploit references
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Technologies
Your stack
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Your stack
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