How severe is CVE-2023-49551?

CVE-2023-49551 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-49551 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-49551?

CVE-2023-49551 affects Cesanta Mjs. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-49551?

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.

Does CVE-2023-49551 have an EU (EUVD) identifier?

Yes. CVE-2023-49551 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-53508.

When was CVE-2023-49551 published?

CVE-2023-49551 was published on 2024-01-02 and last updated on 2026-06-17.

CVE-2023-49551

CVE-2023-49551 is a high-severity vulnerability in Cesanta Mjs with a CVSS 3.x base score of 7.5. 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-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (51st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-53508
Weakness: CWE-20
Affected product: Cesanta Mjs
Published: 2024-01-02
Last modified: 2026-06-17

Description

An issue in Cesanta mjs 2.20.0 allows a remote attacker to cause a denial of service via the mjs_op_json_parse function in the msj.c file.

Frequently asked questions

What is CVE-2023-49551?: An issue in Cesanta mjs 2.20.0 allows a remote attacker to cause a denial of service via the mjs_op_json_parse function in the msj.c file.
How severe is CVE-2023-49551?: CVE-2023-49551 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-49551 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (51st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-49551?: CVE-2023-49551 affects Cesanta Mjs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-49551?: 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.
Does CVE-2023-49551 have an EU (EUVD) identifier?: Yes. CVE-2023-49551 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-53508.
When was CVE-2023-49551 published?: CVE-2023-49551 was published on 2024-01-02 and last updated on 2026-06-17.

References

https://github.com/cesanta/mjs/issues/257

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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