CVE-2026-77399
- Source
- https://cve.org/CVERecord?id=CVE-2026-77399
- Import Source
- https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-77399.json
- JSON Data
- https://api.osv.dev/v1/vulns/CVE-2026-77399
- Aliases
-
- GHSA-qjcq-q7h7-r74v
- Downstream
- Published
- 2026-09-22T18:58:56Z
- Modified
- 2026-10-28T02:30:44Z
- Severity
-
- 6.5 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- icalendar: Denial of service via unbounded VALARM REPEAT expansion
- Details
-
icalendar is an RFC 5545 compatible parser and generator of iCalendar files for Python. From 6.1.0 until 7.2.2, vInt.from_ical 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 Alarms.active reach the unbounded expansion in versions starting with 6.1.0, while Alarm.triggers adds a second affected path starting with 7.0.0. Parsing alone does not trigger the issue, but accessing these properties can consume excessive CPU time and heap memory and terminate or stall a service. This issue is fixed in version 7.2.2.
- Database specific
{ "cna_assigner": "GitHub_M", "cwe_ids": [ "CWE-400", "CWE-834" ], "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77399.json" }- References
-
- https://github.com/collective/icalendar/releases/tag/v7.2.2
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/77xxx/CVE-2026-77399.json
- https://github.com/collective/icalendar/security/advisories/GHSA-qjcq-q7h7-r74v
- https://nvd.nist.gov/vuln/detail/CVE-2026-77399
- https://github.com/collective/icalendar/commit/157f85137c65565a308bbcf4fdcc7d8ebce01267
- https://github.com/collective/icalendar/commit/cddd37226adbc52cca52a399f61d38a378221219
- https://github.com/collective/icalendar/pull/1571
Affected packages
Git / github.com/collective/icalendar
Affected ranges
- Type
- GIT
- Repo
- https://github.com/collective/icalendar
- Events
- Database specific
-
Show details
{ "extracted_events": [ { "range": [ { "introduced": "6.1.0" }, { "fixed": "7.2.2" } ], "source": "AFFECTED_FIELD", "strategy": "StringRangeExpression" }, { "range": [ { "fixed": "157f85137c65565a308bbcf4fdcc7d8ebce01267" } ], "source": "REFERENCES_COMMIT" }, { "range": [ { "fixed": "cddd37226adbc52cca52a399f61d38a378221219" } ], "source": "REFERENCES_COMMIT" }, { "original_tag": "v7.2.2", "range": [ { "fixed": "ad87bcf719fde8088a77c724bc2ae8f09545e0e4" } ], "source": "REFERENCES_TAG" } ] }