CVE-2021-28994
CVSS v3
7.5
HIGH
EPSS Score
2.0 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.
Technical details
- Published
- 2021-03-31
Frequently asked questions
What is CVE-2021-28994?
kopano-ical (formerly zarafa-ical) in Kopano Groupware Core through 8.7.16, 9.x through 9.1.0, 10.x through 10.0.7, and 11.x through 11.0.1 and Zarafa 6.30.x through 7.2.x allows memory exhaustion via long HTTP headers.
Is CVE-2021-28994 actively exploited?
Active exploitation of CVE-2021-28994 has not been confirmed. Its EPSS score was 2.0% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-28994?
CVE-2021-28994 has a CVSS v3 base score of 7.5 (HIGH severity).
Is CVE-2021-28994 affecting your environment?
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