How severe is CVE-2024-45614?

CVE-2024-45614 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2024-45614 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-45614?

CVE-2024-45614 affects Puma. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-45614?

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

Does CVE-2024-45614 have an EU (EUVD) identifier?

Yes. CVE-2024-45614 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-2761.

When was CVE-2024-45614 published?

CVE-2024-45614 was published on 2024-09-19 and last updated on 2026-06-17.

CVE-2024-45614

CVE-2024-45614 is a medium-severity vulnerability in Puma with a CVSS 3.x base score of 5.4. 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-444.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 1% (47th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-2761
Weakness: CWE-444
Affected product: Puma
Published: 2024-09-19
Last modified: 2026-06-17

Description

Puma is a Ruby/Rack web server built for parallelism. In affected versions clients could clobber values set by intermediate proxies (such as X-Forwarded-For) by providing a underscore version of the same header (X-Forwarded_For). Any users relying on proxy set variables is affected. v6.4.3/v5.6.9 now discards any headers using underscores if the non-underscore version also exists. Effectively, allowing the proxy defined headers to always win. Users are advised to upgrade. Nginx has a underscores_in_headers configuration variable to discard these headers at the proxy level as a mitigation. Any users that are implicitly trusting the proxy defined headers for security should immediately cease doing so until upgraded to the fixed versions.

Frequently asked questions

What is CVE-2024-45614?: Puma is a Ruby/Rack web server built for parallelism. In affected versions clients could clobber values set by intermediate proxies (such as X-Forwarded-For) by providing a underscore version of the same header (X-Forwarded_For). Any users relying on proxy set variables is affected. v6.4.3/v5.6.9 now discards any headers using underscores if the non-underscore version also exists. Effectively, allowing the proxy defined headers to always win. Users are advised to upgrade. Nginx has a underscores_in_headers configuration variable to discard these headers at the proxy level as a mitigation. Any users that are implicitly trusting the proxy defined headers for security should immediately cease doing so until upgraded to the fixed versions.
How severe is CVE-2024-45614?: CVE-2024-45614 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2024-45614 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (47th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-45614?: CVE-2024-45614 affects Puma. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-45614?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-45614 have an EU (EUVD) identifier?: Yes. CVE-2024-45614 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-2761.
When was CVE-2024-45614 published?: CVE-2024-45614 was published on 2024-09-19 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:puma:puma:*:*:*:*:*:ruby:*:*

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