CVE-2026-88390: n/a
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.
AI Analysis
Technical Summary
This vulnerability involves a one-byte out-of-bounds write in the Espruino 2v29 JavaScript engine's jslGetTokenValueAsString() function. Specifically, when processing a crafted JavaScript input containing an overlong token, the function writes one byte beyond the allocated JsLex.token buffer. This corrupts the adjacent tokenValue pointer, leading to memory corruption that may cause application instability or denial of service. The issue affects RELEASE/NO_ASSERT builds of Espruino 2v29 at commit bffc6d0. No CVSS score or patch information is provided.
Potential Impact
The out-of-bounds write can corrupt memory adjacent to the token buffer, specifically the tokenValue pointer. This corruption may cause the application to crash or become unavailable, resulting in denial of service. There is no information about remote code execution or other impacts. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted or crafted JavaScript inputs that could trigger this vulnerability. Monitor vendor channels for updates and apply official patches once released.
CVE-2026-88390: n/a
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.
CVSS v3.1
Score 7.7high
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a one-byte out-of-bounds write in the Espruino 2v29 JavaScript engine's jslGetTokenValueAsString() function. Specifically, when processing a crafted JavaScript input containing an overlong token, the function writes one byte beyond the allocated JsLex.token buffer. This corrupts the adjacent tokenValue pointer, leading to memory corruption that may cause application instability or denial of service. The issue affects RELEASE/NO_ASSERT builds of Espruino 2v29 at commit bffc6d0. No CVSS score or patch information is provided.
Potential Impact
The out-of-bounds write can corrupt memory adjacent to the token buffer, specifically the tokenValue pointer. This corruption may cause the application to crash or become unavailable, resulting in denial of service. There is no information about remote code execution or other impacts. No known exploits are reported in the wild.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until a fix is available, avoid processing untrusted or crafted JavaScript inputs that could trigger this vulnerability. Monitor vendor channels for updates and apply official patches once released.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mitre
- Date Reserved
- 2026-09-10T00:00:00.000Z
- State
- PUBLISHED
Threat ID: 6ab5545bf7a7c5410690de35
Added to database: 09/24/2026, 16:48:27 UTC
Last enriched: 09/24/2026, 17:04:04 UTC
Last updated: 09/25/2026, 03:03:47 UTC
Views: 7
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