CVE-2026-86716

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.

CVSS v3 7.3 HIGH
CVSS v2.0 7.5 HIGH

7.3^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact LOW

Scope UNCHANGED

7.5^/10

CVSS v2.0 : HIGH

Vector : AV:N/AC:L/Au:N/C:P/I:P/A:P

Exploitability : 10.0 / Impact : 6.4

Access Vector NETWORK

Access Complexity LOW

Authentication NONE

Confidentiality Impact PARTIAL

Integrity Impact PARTIAL

Availability Impact PARTIAL

References

Link	Resource
https://github.com/cesanta/mjs/
https://github.com/cesanta/mjs/issues/324
https://vuldb.com/cve/CVE-2026-86716
https://vuldb.com/submit/910881
https://vuldb.com/submit/910882
https://vuldb.com/vuln/399773
https://vuldb.com/vuln/399773/cti

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-08 19:20

Updated : 2026-09-08 20:18

NVD link : CVE-2026-86716

Mitre link : CVE-2026-86716

CVE.ORG link : CVE-2026-86716

JSON object : View

Products Affected

No product.

CWE

CWE-119

Improper Restriction of Operations within the Bounds of a Memory Buffer

CWE-122

Heap-based Buffer Overflow

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{"status": "affected", "version": "1.21"}, {"status": "affected", "version": "1.22"}, {"status": "affected", "version": "1.23"}, {"status": "affected", "version": "1.24"}, {"status": "affected", "version": "1.25"}, {"status": "affected", "version": "1.26"}]}]}], "published": "2026-09-08T19:20:17.357", "references": [{"url": "https://github.com/cesanta/mjs/", "source": "cna@vuldb.com"}, {"url": "https://github.com/cesanta/mjs/issues/324", "source": "cna@vuldb.com"}, {"url": "https://vuldb.com/cve/CVE-2026-86716", "source": "cna@vuldb.com"}, {"url": "https://vuldb.com/submit/910881", "source": "cna@vuldb.com"}, {"url": "https://vuldb.com/submit/910882", "source": "cna@vuldb.com"}, {"url": "https://vuldb.com/vuln/399773", "source": "cna@vuldb.com"}, {"url": "https://vuldb.com/vuln/399773/cti", "source": "cna@vuldb.com"}], "vulnStatus": "Deferred", "weaknesses": [{"type": "Secondary", "source": "cna@vuldb.com", "description": [{"lang": "en", "value": "CWE-119"}, {"lang": "en", "value": "CWE-122"}]}], "descriptions": [{"lang": "en", "value": "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."}], "lastModified": "2026-09-08T20:18:53.110", "sourceIdentifier": "cna@vuldb.com"}