{"id":11663,"date":"2026-09-04T18:53:46","date_gmt":"2026-09-04T10:53:46","guid":{"rendered":"https:\/\/www.54iter.cn\/?vuln=cve-2026-55099"},"modified":"2026-09-04T18:53:46","modified_gmt":"2026-09-04T10:53:46","slug":"cve-2026-55099","status":"publish","type":"vuln","link":"https:\/\/www.54iter.cn\/?vuln=cve-2026-55099","title":{"rendered":"CVE-2026-55099 [HIGH] &#8211; icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. Fr"},"content":{"rendered":"<p>icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. From 7.1.0 until 7.1.3, the Component equality method in src\/icalendar\/cal\/component.py compares nested subcomponents with two membership loops, and each membership test invokes the same method on child components, causing O(2^n) work relative to nesting depth. Component.from_ical accepts arbitrarily nested BEGIN:VEVENT blocks without a depth limit, so an attacker can submit a sub-kilobyte .ics file containing equal nested subtrees and trigger the cost when an application performs equality, inequality, membership, deduplication, test-assertion, round-trip, or normalization comparisons. Parsing alone does not trigger the issue, and comparisons that differ early short-circuit, but a few hundred bytes can pin a CPU core for minutes or indefinitely, causing denial of service in calendar sync or import endpoints, invite processing, and other comparison paths. This issue is fixed in version 7.1.3.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. From 7.1.0 until 7.1.3, the Component equality method in src\/icalendar\/cal\/component.py compares nested subcompo<\/p>\n","protected":false},"template":"","meta":[],"categories":[],"tags":[],"class_list":["post-11663","vuln","type-vuln","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/www.54iter.cn\/index.php?rest_route=\/wp\/v2\/vuln\/11663","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=11663"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=11663"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.54iter.cn\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=11663"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}