CVE-2026-73311 — XenForo < 2.3.13 OAuth2 Authorization Code Reuse
XenForo before 2.3.13 contains an OAuth2 authorization code reuse vulnerability that allows attackers to obtain unauthorized token pairs by submitting a previously used authoriz…
Published: 2026-09-08 · CVSS: 9.1 · CVSS 4.0
XenForo before 2.3.13 contains an OAuth2 authorization code reuse vulnerability that allows attackers to obtain unauthorized token pairs by submitting a previously used authorization code. Attackers can exploit the failure to invalidate or mark authorization codes as consumed after initial token issuance to receive an independent token pair for the same user and scopes, bypassing the single-use guarantee of the OAuth2 authorization code flow.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7