VULNERABILITY INTELLIGENCE
CVE-2021-31875
CVSS score9.8 CRITICAL
EPSS probability2.17%
CISA KEVNot currently listed
Published2021-04-29
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Description
In mjs_json.c in Cesanta MongooseOS mJS 1.26, a maliciously formed JSON string can trigger an off-by-one heap-based buffer overflow in mjs_json_parse, which can potentially lead to redirection of control flow. NOTE: the original reporter disputes the significance of this finding because "there isn’t very much of an opportunity to exploit this reliably for an information leak, so there isn’t any real security impact."
Weakness classification
- CWE-193: Off-by-one Error
- CWE-787: Out-of-bounds Write
Primary references
- cve@mitre.org — Patch, Third Party Advisory
- cve@mitre.org — Release Notes, Third Party Advisory
- cve@mitre.org — Exploit, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Patch, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Release Notes, Third Party Advisory
- af854a3a-2127-422b-91ae-364da2661108 — Exploit, Third Party Advisory