CVE-2021-46523
CVE-2021-46523 is a high-severity vulnerability in Cesanta Mjs with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.
Key facts
- Severity: High (CVSS 3.x base score 7.8)
- CVSS v2: 6.8
- EPSS exploit prediction: 1% (50th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-787
- Affected product: Cesanta Mjs
- Published:
- Last modified:
Description
Cesanta MJS v2.20.0 was discovered to contain a heap buffer overflow via to_json_or_debug at mjs/src/mjs_json.c.
Frequently asked questions
- What is CVE-2021-46523?
- Cesanta MJS v2.20.0 was discovered to contain a heap buffer overflow via to_json_or_debug at mjs/src/mjs_json.c.
- How severe is CVE-2021-46523?
- CVE-2021-46523 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2021-46523 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-46523?
- CVE-2021-46523 affects Cesanta Mjs. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-46523?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2021-46523 published?
- CVE-2021-46523 was published on 2022-01-27 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:cesanta:mjs:2.20.0:*:*:*:*:*:*:*
More vulnerabilities in Cesanta Mjs
- CVE-2023-50044 — Critical (CVSS 9.8): Cesanta MJS 2.20.0 has a getprop_builtin_foreign out-of-bounds read if a Built-in API name occurs in a substring of an…
- CVE-2023-43338 — Critical (CVSS 9.8): Cesanta mjs v2.20.0 was discovered to contain a function pointer hijacking vulnerability via the function…
- CVE-2021-46527 — High (CVSS 7.8): Cesanta MJS v2.20.0 was discovered to contain a heap buffer overflow via mjs_get_cstring at src/mjs_string.c.
- CVE-2021-46526 — High (CVSS 7.8): Cesanta MJS v2.20.0 was discovered to contain a global buffer overflow via snquote at src/mjs_json.c.
- CVE-2021-46525 — High (CVSS 7.8): Cesanta MJS v2.20.0 was discovered to contain a heap-use-after-free via mjs_apply at src/mjs_exec.c.
- CVE-2021-46524 — High (CVSS 7.8): Cesanta MJS v2.20.0 was discovered to contain a heap buffer overflow via snquote at mjs/src/mjs_json.c.
All CVEs affecting Cesanta Mjs →
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