How severe is CVE-2023-49952?

CVE-2023-49952 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 high, and availability none.

Is CVE-2023-49952 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-49952?

CVE-2023-49952 affects Joinmastodon Mastodon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-49952?

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-2023-49952 have an EU (EUVD) identifier?

Yes. CVE-2023-49952 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-53847.

When was CVE-2023-49952 published?

CVE-2023-49952 was published on 2024-11-18 and last updated on 2026-06-17.

CVE-2023-49952

CVE-2023-49952 is a high-severity vulnerability in Joinmastodon Mastodon 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-79.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 0% (37th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-53847
Weakness: CWE-79
Affected product: Joinmastodon Mastodon
Published: 2024-11-18
Last modified: 2026-06-17

Description

Mastodon 4.1.x before 4.1.17 and 4.2.x before 4.2.9 allows a bypass of rate limiting via a crafted HTTP request header.

Frequently asked questions

What is CVE-2023-49952?: Mastodon 4.1.x before 4.1.17 and 4.2.x before 4.2.9 allows a bypass of rate limiting via a crafted HTTP request header.
How severe is CVE-2023-49952?: CVE-2023-49952 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 high, and availability none.
Is CVE-2023-49952 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (37th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-49952?: CVE-2023-49952 affects Joinmastodon Mastodon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-49952?: 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-2023-49952 have an EU (EUVD) identifier?: Yes. CVE-2023-49952 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-53847.
When was CVE-2023-49952 published?: CVE-2023-49952 was published on 2024-11-18 and last updated on 2026-06-17.

References

Affected products (1)

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

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