How severe is CVE-2023-36462?

CVE-2023-36462 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2023-36462 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-36462?

CVE-2023-36462 affects Joinmastodon Mastodon. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-36462?

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

When was CVE-2023-36462 published?

CVE-2023-36462 was published on 2023-07-06 and last updated on 2026-06-17.

CVE-2023-36462

CVE-2023-36462 is a medium-severity vulnerability in Joinmastodon Mastodon 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-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.4)
EPSS exploit prediction: 1% (45th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Joinmastodon Mastodon
Published: 2023-07-06
Last modified: 2026-06-17

Description

Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 2.6.0 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker can craft a verified profile link using specific formatting to conceal arbitrary parts of the link, enabling it to appear to link to a different URL altogether. The link is visually misleading, but clicking on it will reveal the actual link. This can still be used for phishing, though, similar to IDN homograph attacks. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.

Frequently asked questions

What is CVE-2023-36462?: Mastodon is a free, open-source social network server based on ActivityPub. Starting in version 2.6.0 and prior to versions 3.5.9, 4.0.5, and 4.1.3, an attacker can craft a verified profile link using specific formatting to conceal arbitrary parts of the link, enabling it to appear to link to a different URL altogether. The link is visually misleading, but clicking on it will reveal the actual link. This can still be used for phishing, though, similar to IDN homograph attacks. Versions 3.5.9, 4.0.5, and 4.1.3 contain a patch for this issue.
How severe is CVE-2023-36462?: CVE-2023-36462 has a CVSS 3.x base score of 5.4, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2023-36462 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (45th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-36462?: CVE-2023-36462 affects Joinmastodon Mastodon. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-36462?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2023-36462 published?: CVE-2023-36462 was published on 2023-07-06 and last updated on 2026-06-17.

References

Affected products (1)

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

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