CVE-2021-41585

mediumpriority · track · 31EPSS 0.025 · 85 %ileEURUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.49% (85th) EPSS

CVSS 5 · medium

Is it mine?

5 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · fstec_bdu · nvd

EPSS · scored 2026-10-27

Improper Input Validation vulnerability in accepting socket connections in Apache Traffic Server allows an attacker to make the server stop accepting new connections. This issue affects Apache Traffic Server 5.0.0 to 9.1.0.

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

v3.17.5highAV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU

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-20USprimaryCWE-20US

affected products (5)

Products and version ranges known to be affected.

Apache Software Foundation Apache Traffic Server≤ 7.0.0 to 9.1.0enisa_euvdEU
Apache Software Foundation Traffic Server8.0.0 → 8.1.2fstec_bduRU
Apache Software Foundation Traffic Server9.0.0 → 9.1.0fstec_bduRU
apache traffic server8.0.0 → 8.1.2nvdUScpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
apache traffic server9.0.0 → 9.1.0nvdUScpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*

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 2021-11-03modified 2026-06-17

related (25,193)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2026-88771US	critical9.8OT critical	82.2% (100th)	KEV	2026-09-27
Improper input validation vulnerability in Citrix NetScaler ADC and Citrix NetScaler Gateway. This issue affects ADC: before 14.1-73.37, before 13.1-64.23, before 14.1-73.37 FIPS,…
CVE-2026-93952US	—OT critical	1.38% (72nd)	KEV	2026-09-22
VeloCloud Orchestrator (VCO) on-prem has a security issue where this issue may allow a remote attacker to access privileged internal functionality and impact the VCO host. Successf…
CVE-2026-12569US	critical9.8OT critical	46.0% (99th)	KEV	2026-06-18
A critical remote code execution (RCE) vulnerability has been reported in PTC Windchill PDMlink and PTC FlexPLM. The vulnerability may be exploited through the deserialization of u…
CVE-2026-34910US	—OT critical	90.0% (100th)	KEV	2026-05-22
A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS devices to execute a Command Injection.
CVE-2026-6973US	—OT critical	34.5% (98th)	KEV	2026-05-07
An Improper Input Validation in Ivanti EPMM before versions 12.6.1.1, 12.7.0.1, and 12.8.0.1 allows a remotely authenticated user with administrative access to achieve remote code…

+25188 more

references (6)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan