Interpreter crash via unterminated string length scan
Published May 9, 2023 · Updated Jan 29, 2025
Heap buffer overflow in Cesanta MJS 1.26 allows local users to crash the interpreter by processing a crafted local input file. The mjs_mk_string function calls strlen on a 93-byte parsed string buffer without an in-bounds NUL terminator, causing a heap out-of-bounds read. Local code-execution access is required to supply the file and invoke MJS; the demonstrated consequence is an AddressSanitizer abort of the interpreter process.
Summary
What happened
Heap buffer overflow in Cesanta MJS 1.26 allows local users to crash the interpreter by processing a crafted local input file. The mjs_mk_string function calls strlen on a 93-byte parsed string buffer without an in-bounds NUL terminator, causing a heap out-of-bounds read. Local code-execution access is required to supply the file and invoke MJS; the demonstrated consequence is an AddressSanitizer abort of the interpreter process.
The record
- CVE
- CVE-2023-30087
- Published
- May 9, 2023
- Updated
- Jan 29, 2025
- Vendor
- Unknown vendor
- Product
- Unknown product
- Classifications
- CWE-787, T1499.004
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- May 9, 2023CVE publishedPublication date reported by the CVE source.
- Jan 29, 2025Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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What conditions does exploitation require?
What is affected?
Affected products and versions are unavailable in this record.
Attacks
What attackers are doing with it
Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.
Public exploit references
- Heap buffer overflow in mjs_mk_string reproducerproof of concept · demonstrated
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Technologies
Your stack
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Your stack
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