CVE-2021-33600
Denial of Service Vulnerability in Web Interface of F-Secure Internet Gatekeeper
- Published
- Updated
- Reserved
- Assigned by
- F-SecureUS
Description
A denial-of-service (DoS) vulnerability was discovered in the web user interface of F-Secure Internet Gatekeeper. The vulnerability occurs because of an attacker can trigger assertion via malformed HTTP packet to web interface. An unauthenticated attacker could exploit this vulnerability by sending a large username parameter. A successful exploitation could lead to a denial-of-service of the product.
Timeline
ID reserved
By F-SecureUS
- 4 months later
· 4 months later
Published
- 3 years later
· 3 years later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
| Scored by | CVSS | Score | Vector |
|---|---|---|---|
| F-SecureUSCNA (assigner) | 3.1 | Medium5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVDNVD · Modified | 3.1 | High7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
- EPSS (exploitation in 30 days)
- 0.61% · top 51% of all CVEs (7 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.4.
Weakness
- Denial of Service Vulnerability in Web Interface of F-Secure Internet Gatekeeper
- CWE-617 (opens in a new tab)All about CWE-617 and its CVEs
Affected products
F-Secure · F-Secure Internet Gatekeeper
- affected 5 Series All Version
What to do
Solution: FIX: Hotfix 9 will be published to fix this vulnerability. Download and instructions available at: https://www.f-secure.com/en/business/downloads/internet-gatekeeper
References (2)
- https://www.f-secure.com/en/business/programs/vulnerability-reward-program/hall-of-fame (opens in a new tab)x_refsource_MISCx_transferred
- https://www.f-secure.com/en/business/support-and-downloads/security-advisories/cve-2021-33600 (opens in a new tab)x_refsource_MISCx_transferred
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://trackcve.app/cve/CVE-2021-33600)Record last updated .