How severe is CVE-2023-4540?

CVE-2023-4540 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-2023-4540 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-4540?

CVE-2023-4540 affects Daurnimator Lua-http. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-4540?

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-2023-4540 published?

CVE-2023-4540 was published on 2023-09-05 and last updated on 2026-06-17.

CVE-2023-4540

CVE-2023-4540 is a high-severity vulnerability in Daurnimator Lua-http 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-755.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (57th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-755
Affected product: Daurnimator Lua-http
Published: 2023-09-05
Last modified: 2026-06-17

Description

Improper Handling of Exceptional Conditions vulnerability in Daurnimator lua-http library allows Excessive Allocation and a denial of service (DoS) attack to be executed by sending a properly crafted request to the server. Such a request causes the program to enter an infinite loop. This issue affects lua-http: all versions before commit ddab283.

Frequently asked questions

What is CVE-2023-4540?: Improper Handling of Exceptional Conditions vulnerability in Daurnimator lua-http library allows Excessive Allocation and a denial of service (DoS) attack to be executed by sending a properly crafted request to the server. Such a request causes the program to enter an infinite loop. This issue affects lua-http: all versions before commit ddab283.
How severe is CVE-2023-4540?: CVE-2023-4540 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-2023-4540 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (57th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-4540?: CVE-2023-4540 affects Daurnimator Lua-http. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-4540?: 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-2023-4540 published?: CVE-2023-4540 was published on 2023-09-05 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:daurnimator:lua-http:0.4:*:*:*:*:lua:*:*

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