Heap corruption via undersized alternate signal stack
Published Dec 11, 2024 · Updated Dec 12, 2024
Heap-based out-of-bounds writes in Mullvad VPN client 2024.6 Desktop, 2024.8 iOS, and 2024.8-beta1 Android allow remote attackers to corrupt memory. The enable() function in exception_logging/unix.rs allocates only libc::SIGSTKSZ bytes on the heap for the alternate signal stack and provides no guard page, so handler stack exhaustion overwrites adjacent heap data. Exploitation requires another fault to deliver a handled signal in the right context; successful heap control grants code execution, but X41 considers that outcome non-trivial.
Summary
What happened
Heap-based out-of-bounds writes in Mullvad VPN client 2024.6 Desktop, 2024.8 iOS, and 2024.8-beta1 Android allow remote attackers to corrupt memory. The enable() function in exception_logging/unix.rs allocates only libc::SIGSTKSZ bytes on the heap for the alternate signal stack and provides no guard page, so handler stack exhaustion overwrites adjacent heap data. Exploitation requires another fault to deliver a handled signal in the right context; successful heap control grants code execution, but X41 considers that outcome non-trivial.
The record
- CVE
- CVE-2024-55884
- Published
- Dec 11, 2024
- Updated
- Dec 12, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-400, CWE-787
- Attack vector
- network
- Privileges
- unauthenticated
Timeline
How it unfolded
- Dec 11, 2024CVE publishedPublication date reported by the CVE source.
- Dec 12, 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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Public exploit references
No public exploit references are available in this record.
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Technologies
Your stack
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Your stack
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