CVE-2026-77399

icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. From 6.1.0 until 7.2.2, vInt.fromical accepts an attacker-controlled VALARM REPEAT value and applications that request alarm times can eagerly expand it without an application-level limit. Alarms.times and...

CVE-2026-77399

The icalendar library for Python, versions 6.1.0 through 7.2.2 , is vulnerable to a Denial of Service (DoS) . The vInt.from_ical function accepts an attacker-controlled VALARM REPEAT value, allowing applications to eagerly expand it without an application-level limit. While parsing alone does not...

CVE-2026-77399 icalendar: Denial of service via unbounded VALARM REPEAT expansion

icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. From 6.1.0 until 7.2.2, vInt.fromical accepts an attacker-controlled VALARM REPEAT value and applications that request alarm times can eagerly expand it without an application-level limit. Alarms.times and...