CSRF in phpBB

CVE-2026-48612

Improper state verification in the OAuth implementation could allow an attacker to manipulate the authentication flow and cause a victim’s account to be linked to an attacker-controlled account. This can result in unauthorized account linking and potential account takeover.

Vulnerability class: CSRF (Cross-Site Request Forgery)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.0 (High). Vector: CVSS:3.0/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.002 (6.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 7th percentile — 6.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-48612: held from 0.001 to 0.002.

EPSS over last 30 days · oldest: 0.001 · newest: 0.002 · change: +0.001

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-48612?
CVE-2026-48612 is a high-severity vulnerability in phpBB, classified under Cross-Site Request Forgery (CSRF). CVSS score: 8.0/10. Published 2026-06-12.
How severe is CVE-2026-48612?
High severity. CVSS v3 base score is 8.0 out of 10.