How severe is CVE-2024-34535?

CVE-2024-34535 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2024-34535 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-34535?

CVE-2024-34535 affects Joinmastodon Mastodon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-34535?

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

Does CVE-2024-34535 have an EU (EUVD) identifier?

Yes. CVE-2024-34535 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-35151.

When was CVE-2024-34535 published?

CVE-2024-34535 was published on 2024-10-03 and last updated on 2026-06-17.

CVE-2024-34535

CVE-2024-34535 is a medium-severity vulnerability in Joinmastodon Mastodon with a CVSS 3.x base score of 5.9. 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 5.9)
EPSS exploit prediction: 0% (29th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-35151
Weakness: CWE-444
Affected product: Joinmastodon Mastodon
Published: 2024-10-03
Last modified: 2026-06-17

Description

In Mastodon 4.1.6, API endpoint rate limiting can be bypassed by setting a crafted HTTP request header.

Frequently asked questions

What is CVE-2024-34535?: In Mastodon 4.1.6, API endpoint rate limiting can be bypassed by setting a crafted HTTP request header.
How severe is CVE-2024-34535?: CVE-2024-34535 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2024-34535 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (29th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-34535?: CVE-2024-34535 affects Joinmastodon Mastodon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-34535?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-34535 have an EU (EUVD) identifier?: Yes. CVE-2024-34535 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-35151.
When was CVE-2024-34535 published?: CVE-2024-34535 was published on 2024-10-03 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:joinmastodon:mastodon:*:*:*:*:*:*:*:*

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