CVE-2026-34460
CVE-2026-34460 is a medium-severity vulnerability 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-302.
Key facts
- Severity: Medium (CVSS 3.x base score 5.4)
- EPSS exploit prediction: 0% (2nd percentile)
- Actively exploited: Not listed in CISA KEV
- EU (EUVD) id: EUVD-2026-33960
- Weakness: CWE-302
- Published:
- Last modified:
Description
NamelessMC is website software for Minecraft servers. In versions 2.2.4 and prior, the OAuth callback handling does not validate the state parameter server-side before exchanging the authorization code. This allows an attacker to capture a valid OAuth callback URL for their own account and cause a victim's browser to navigate to it, resulting in the victim's session being authenticated as the attacker-linked account (OAuth login CSRF / session swapping). This is patched in version 2.2.5.
Frequently asked questions
- What is CVE-2026-34460?
- NamelessMC is website software for Minecraft servers. In versions 2.2.4 and prior, the OAuth callback handling does not validate the state parameter server-side before exchanging the authorization code. This allows an attacker to capture a valid OAuth callback URL for their own account and cause a victim's browser to navigate to it, resulting in the victim's session being authenticated as the attacker-linked account (OAuth login CSRF / session swapping). This is patched in version 2.2.5.
- How severe is CVE-2026-34460?
- CVE-2026-34460 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-2026-34460 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (2nd percentile), an estimate of the probability of exploitation in the next 30 days.
- How do I fix CVE-2026-34460?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- Does CVE-2026-34460 have an EU (EUVD) identifier?
- Yes. CVE-2026-34460 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-33960.
- When was CVE-2026-34460 published?
- CVE-2026-34460 was published on 2026-06-02 and last updated on 2026-06-17.
References
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