Kernel crash via unbounded escape-sequence arguments
Published Aug 10, 2023 · Updated Oct 9, 2024
Out-of-bounds memory access in OpenBSD 7.3 before errata 014 allows local users to crash the kernel via crafted terminal escapes. In sys/dev/wscons/wsemul_sun.c and wsemul_vt100.c, DCS and CSI parsers increment nargs for each semicolon beyond their argument-array bounds, so later handling reads unintended kernel memory. A local user must write the crafted sequence to a wscons console; the documented consequence is a kernel crash, not data disclosure or code execution.
Summary
What happened
Out-of-bounds memory access in OpenBSD 7.3 before errata 014 allows local users to crash the kernel via crafted terminal escapes. In sys/dev/wscons/wsemul_sun.c and wsemul_vt100.c, DCS and CSI parsers increment nargs for each semicolon beyond their argument-array bounds, so later handling reads unintended kernel memory. A local user must write the crafted sequence to a wscons console; the documented consequence is a kernel crash, not data disclosure or code execution.
The record
- CVE
- CVE-2023-40216
- Published
- Aug 10, 2023
- Updated
- Oct 9, 2024
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-862, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 10, 2023CVE publishedPublication date reported by the CVE source.
- Oct 9, 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.
Published CVSS scores
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Attacks
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Public exploit references
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Technologies
Your stack
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Your stack
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