{"id":26248,"date":"2026-09-18T12:32:42","date_gmt":"2026-09-18T04:32:42","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-77164"},"modified":"2026-09-18T12:32:42","modified_gmt":"2026-09-18T04:32:42","slug":"cve-2026-77164","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-77164","title":{"rendered":"CVE-2026-77164 [MEDIUM] &#8211; Circles&#8217; remote-instance signature verification fetches the attacker-supplied keyId URL be"},"content":{"rendered":"<p>Circles&#8217; remote-instance signature verification fetches the attacker-supplied keyId URL before trust in the remote instance is established, and explicitly allows local\/private addresses for this request, bypassing Nextcloud&#8217;s core SSRF protections. The public, unauthenticated endpoints POST \/apps\/circles\/event\/ and POST \/apps\/circles\/incoming\/ reach this code path, allowing any unauthenticated user to force the server to issue a GET request to an internal address.<\/p>\n<p>The response body of the internal request is never returned to the requester, so this is blind SSRF: an attacker can determine whether an internal service is reachable, but cannot read its response contents through this endpoint alone.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Circles&#8217; remote-instance signature verification fetches the attacker-supplied keyId URL before trust in the remote instance is established, and explicitly allows local\/private addresses for this reque<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-26248","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/26248","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln"}],"about":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/types\/vuln"}],"wp:attachment":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=26248"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=26248"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=26248"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}