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No exploitation reported

CVE-2021-28994

No exploitation reported by the sources we read.

  • Published2021-03-31
  • WeaknessCWE-770

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

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.

Timeline

dates in UTC
  1. 2021-03-3123:15CVE publishedNVD

Versions per branch

NVD
Zarafa
BranchAffectedFixed in
7.2≥ 6.30.0, ≤ 7.2.6no fix published
Kopano groupware core
BranchAffectedFixed in
8.7≤ 8.7.16no fix published
9.x≥ 9.0.0, ≤ 9.1.0no fix published
10.0≥ 10.0.0, ≤ 10.0.7no fix published
11.0≥ 11.0.0, ≤ 11.0.1no fix published

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • kopanocoreUbuntu:Pro:18.04:LTSall versions · no fixed version listed
  • kopanocoreUbuntu:22.04:LTSall versions · no fixed version listed
  • kopanocoreUbuntu:20.04:LTSall versions · no fixed version listed

Vendor advisories

  • CVE-2021-28994 Red Hat Product Security

    zarafa: Remote DoS by memory exhaustion in zarafa-ical component

Full record on NVD

Fix

No fix published by the sources we read yet. NVD record

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published
2021-03-31
Last Modified
2026-06-17
NVD status
Modified
GitHub Advisory
GHSA-796m-wc5q-p6qj

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 2026-11-08, 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), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

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Sources for this record