CVE-2026-88388

High

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.

SeverityHigh
CVSS7.5
Exploit probability—
ProductEspruino
PublishedSep 24, 2026
First seenSep 24, 2026
Weakness typeCWE-121CWE-121

How to fix

Sources list no fixed version or patch link for this vulnerability.

Affected products

ProductAffected versionsFixed in
Espruino2v29—

Check your version

Choose the product and enter the version you run to see whether it falls in the affected range.

In the Intelligence 360 plan

Attack Surface Management

See the assets tied to your domains, the technologies they run and known vulnerabilities in one list.

CVE-2026-88388 · Espruino · Dark Radar