CVE-2026-86716

Cesanta mJS mjs_tok.c skip_spaces_and_comments heap-based overflow

HIGH
7.3
CVSS Score
Published: September 8, 2026 at 06:45 PM UTC
Updated: September 8, 2026 at 08:18 PM UTC
1 product affected across 1 vendormJS

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Severity
HIGH7.3
Exploit prediction
EPSS 0.6%
SSVC
PoC

Description

A vulnerability was determined in Cesanta mJS up to 1.26. Affected is the function skip_spaces_and_comments of the file src/mjs_tok.c. Executing a manipulation can lead to heap-based buffer overflow. The attack can be launched remotely. The exploit has been publicly disclosed and may be utilized. The project was informed of the problem early through an issue report but has not responded yet.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

Remediation

No guide yet

No remediation guidance has been written for this CVE yet, and no fixed version or vendor advisory is recorded against it.

References (7)

VDB EntryTechnical Description
Source: cverecord
https://vuldb.com/vuln/399773
SignaturePermissions Required
Source: cverecord
https://vuldb.com/vuln/399773/cti
Third Party Advisory
Source: cverecord
https://vuldb.com/cve/CVE-2026-86716
Third Party Advisory
Source: cverecord
https://vuldb.com/submit/910881
Third Party Advisory
Source: cverecord
https://vuldb.com/submit/910882
ExploitIssue Tracking
Source: cverecord
https://github.com/cesanta/mjs/issues/324
Product
Source: cverecord
https://github.com/cesanta/mjs/

SSVC — Action Prioritization

SSVCPoCAutomatablePartial impact

SSVC signals action urgency (what to patch first), separate from CVSS which measures severity.

CVSS

7.3HIGHVulDB
Vector?

Quick Info

StatusDEFERRED
CWE
CWE-122CWE-119

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