Login Request a demo
High severity · published Jun 12, 2026
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…
8.0
CVSS
0.1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.0/AV:N/AC:H/PR:L/UI:R/S:C/C:H/I:H/A:H
Attack vector
Network
Complexity
High
Privileges
Low
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Changed
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 2% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
PH
phpBB · phpBB
3.3.0 through 3.3.16 · source: vendor
Affected product
PH
phpBB
phpBB
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-48612
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-48612
www.phpbb.com
https://www.phpbb.com/community/viewtopic.php?t=2672170
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