CVE-2021-33600

mediumpriority · track · 30EPSS 0.006 · 49 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

0.61% (49th) EPSS

CVSS 5 · medium

Is it mine?

3 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.5

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–7.5

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9

v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6

v3.15.4mediumAV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · FSTEC (BDU) RU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · ENISA EU

v3.15.4mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:Nsecondary · cve-notifications-us@f-secure.comexploitability 2.3 · impact 2.7

v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-617USprimaryCWE-20USCWE-617US

affected products (3)

Products and version ranges known to be affected.

F-Secure F-Secure Internet Gatekeeper≤ 5 Series All Versionenisa_euvdEU
F-Secure Corporation F-Secure Internet Gatekeeper5.10 → 5.50.47fstec_bduRU
f-secure internet gatekeeper5.10 → 5.50.47nvdUScpe:2.3:a:f-secure:internet_gatekeeper:*:*:*:*:*:*:*:*

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu nvd NVD CVE.org MITRE

published 2021-09-28modified 2026-06-17

related (1,031)

Related entries.

ID	severity	EPSS	exploitable	published
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buffer.c in named in ISC BIND 9 before 9.9.9-P3, 9.10.x before 9.10.4-P3, and 9.11.x before 9.11.0rc3 does not properly construct responses, which allows remote attackers to cause…
CVE-2021-25216US	critical9.8	83.0% (100th)	—	2021-04-29
In BIND 9.5.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.11.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.…
CVE-2020-8617US	medium5.9	93.4% (100th)	Exploit	2020-05-19
Using a specially-crafted message, an attacker may potentially cause a BIND server to reach an inconsistent state if the attacker knows (or successfully guesses) the name of a TSIG…
CVE-2018-5740US	high7.5	59.6% (99th)	Exploit	2019-01-16
"deny-answer-aliases" is a little-used feature intended to help recursive server operators protect end users against DNS rebinding attacks, a potential method of circumventing the…

+1026 more

references (8)

External citations — patches, advisories, analysis.

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