Description
Espruino 2v29 (commit bffc6d0) contains a stack-based buffer overflow vulnerability in the JavaScript error stack-trace handling path on 64-bit builds. A remote attacker can supply JavaScript input that triggers an exception and reaches jslPrintTokenLineMarker(), which passes the address of a 4-byte int column variable to jsvGetLineAndCol() as a size_t pointer. jsvGetLineAndCol() performs an 8-byte write through the mismatched pointer, overwriting adjacent stack memory.
References1
Metrics
- CVSS 3.1
-
7.5
HIGH
Score source: CNA
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - EPSS — exploit probability
- 0% percentile: 25 · as of 9 November 2026
- CWE
- CWE-121
Could this be exploited in your environment?
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