Memory corruption via unconstrained property return types
Published Feb 9, 2021 · Updated Aug 3, 2024
Memory-safety flaw in the xcb crate before 1.0.0 allows remote attackers controlling an X server to trigger undefined behavior. The xcb::xproto::GetPropertyReply::value function casts server-supplied bytes into a slice of an unconstrained caller-selected type, including types whose bit patterns or alignment are invalid. Exploitation requires a client application to connect to an attacker-controlled X server and invoke value with a type other than u8, u16, or u32, exposing the process to memory corruption or data disclosure.
Summary
What happened
Memory-safety flaw in the xcb crate before 1.0.0 allows remote attackers controlling an X server to trigger undefined behavior. The xcb::xproto::GetPropertyReply::value function casts server-supplied bytes into a slice of an unconstrained caller-selected type, including types whose bit patterns or alignment are invalid. Exploitation requires a client application to connect to an attacker-controlled X server and invoke value with a type other than u8, u16, or u32, exposing the process to memory corruption or data disclosure.
The record
- CVE
- CVE-2021-26956
- Published
- Feb 9, 2021
- Updated
- Aug 3, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-657, T1203
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Feb 9, 2021CVE publishedPublication date reported by the CVE source.
- Aug 3, 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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