Description
An out-of-bounds write vulnerability in jslGetTokenValueAsString() in Espruino 2v29 (commit bffc6d0) allows crafted JavaScript input containing an overlong token to trigger a one-byte write beyond the JsLex.token buffer in RELEASE/NO_ASSERT builds. The out-of-bounds write corrupts the adjacent tokenValue pointer, resulting in memory corruption and potentially causing application crashes or denial of service.
References3
Metrics
- CVSS 3.1
-
7.7
HIGH
Score source: CNA
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H - EPSS — exploit probability
- 0% percentile: 7 · as of 9 November 2026
- CWE
- CWE-787
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