How severe is CVE-2020-24349?

CVE-2020-24349 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2020-24349 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2020-24349?

CVE-2020-24349 affects F5 Njs. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2020-24349?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2020-24349 published?

CVE-2020-24349 was published on 2020-08-13 and last updated on 2026-06-17.

CVE-2020-24349

CVE-2020-24349 is a medium-severity vulnerability in F5 Njs with a CVSS 3.x base score of 5.5. 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-416.

Key facts

Severity: Medium (CVSS 3.x base score 5.5)
CVSS v2: 2.1
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-416
Affected product: F5 Njs
Published: 2020-08-13
Last modified: 2026-06-17

Description

njs through 0.4.3, used in NGINX, allows control-flow hijack in njs_value_property in njs_value.c. NOTE: the vendor considers the issue to be "fluff" in the NGINX use case because there is no remote attack surface.

Frequently asked questions

What is CVE-2020-24349?: njs through 0.4.3, used in NGINX, allows control-flow hijack in njs_value_property in njs_value.c. NOTE: the vendor considers the issue to be "fluff" in the NGINX use case because there is no remote attack surface.
How severe is CVE-2020-24349?: CVE-2020-24349 has a CVSS 3.x base score of 5.5, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2020-24349 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2020-24349?: CVE-2020-24349 affects F5 Njs. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2020-24349?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2020-24349 published?: CVE-2020-24349 was published on 2020-08-13 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:f5:njs:*:*:*:*:*:*:*:*

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