CVE-2021-42009

mediumpriority · track · 18EPSS 0.028 · 87 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

2.82% (87th) EPSS

CVSS 4 · medium

Is it mine?

4 products

Check your exposure

Who says so?

4 sources

cnnvd · enisa_euvd · osv · nvd

EPSS · scored 2026-10-24

An authenticated Apache Traffic Control Traffic Ops user with Portal-level privileges can send a request with a specially-crafted email subject to the /deliveryservices/request Traffic Ops endpoint to send an email, from the Traffic Ops server, with an arbitrary body to an arbitrary email address. Apache Traffic Control 5.1.x users should upgrade to 5.1.3 or 6.0.0. 4.1.x users should upgrade to 5.1.3.

cvss

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

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode

v2.04mediumAV:N/AC:L/Au:S/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8 · impact 2.9

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 2.8 · impact 1.4

v3.14.3mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:Nsecondary · OSV

v3.14mediumCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-20USprimaryCWE-20US

affected products (4)

Products and version ranges known to be affected.

Apache Software Foundation Apache Traffic Control4.0.0 → Apache Traffic Control*enisa_euvdEU
apache traffic control4.1.0 → 5.1.3nvdUScpe:2.3:a:apache:traffic_control:*:*:*:*:*:*:*:*
Go github.com/apache/trafficcontrol< 5.1.3osvUSpkg:golang/github.com/apache/trafficcontrol
Go github.com/apache/trafficcontrol< 5.1.3+incompatibleosvUSpkg:golang/github.com/apache/trafficcontrol

advisories (2)

Vendor and ecosystem advisories describing this.

GHSA-gw97-f6h8-gm94Email relay in Apache Traffic Control2021-10-13ghsa · osvUS
An authenticated Apache Traffic Control Traffic Ops user with Portal-level privileges can send a request with a specially-crafted email subject to the /deliveryservices/request Traffic Ops endpoint to send an email, from the Traffic Ops server, with an arbitrary body to an arbitrary email address. Apache Traffic Control 5.1.x users should upgrade to 5.1.3 or 6.0.0. 4.1.x users should upgrade to 5.1.3.
GO-2022-0602Email relay in Apache Traffic Control in github.com/apache/trafficcontrol2024-08-21vendor · osvUS
Email relay in Apache Traffic Control in github.com/apache/trafficcontrol

also known as (5)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd osv nvd NVD CVE.org MITRE

published 2021-10-12modified 2026-06-17

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+25133 more

references (17)

External citations — patches, advisories, analysis.

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