Apache Traffic Control vulnerable to Slowloris-style Denial of Service attack

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS

• CVE-2017-7670: 4.67% estimated exploitation activity in the next 30 days; percentile 91.78 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

The Traffic Router component of the incubating Apache Traffic Control project is vulnerable to a Slowloris style Denial of Service attack. TCP connections made on the configured DNS port will remain in the ESTABLISHED state until the client explicitly closes the connection or Traffic Router is restarted. If connections remain in the ESTABLISHED state indefinitely and accumulate in number to match the size of the thread pool dedicated to processing DNS requests, the thread pool becomes exhausted. Once the thread pool is exhausted, Traffic Router is unable to service any DNS request, regardless of transport protocol.

Published by the source

13 May 2022, 01:09 UTC

Last modified by the source

9 Jul 2025, 15:40 UTC

Source last checked

26 Oct 2026, 15:09 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-f2wr-c4c4-xjg7

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# Patch Next advisory brief: CVE-2017-7670

Advisory: Apache Traffic Control vulnerable to Slowloris-style Denial of Service attack
IDs: CVE-2017-7670, GHSA-f2wr-c4c4-xjg7
Record: https://patchnext.com/advisories/cve-2017-7670 (revision 1, source checked 26 Oct 2026, 15:09 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/apache/trafficcontrol 2.1.0-RC1, 2.0.0, 1.8.1, 1.1.4-0.20170531185407-738c10fa1b58, 0.0.0-20170531185407-738c10fa1b58. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/apache/trafficcontrol: affected >= 2.0.0-RC0, < 2.0.0; >= 2.1.0-RC0, <= 2.1.0-RC0; < 0.0.0-20170531185407-738c10fa1b58; >= 1.1.4, < 1.8.1; < 1.1.4-0.20170531185407-738c10fa1b58; fixed in 1.8.1, 1.1.4-0.20170531185407-738c10fa1b58, 0.0.0-20170531185407-738c10fa1b58, 2.0.0, 2.1.0-RC1

## Suggested inspection (read-only)
- Go github.com/apache/trafficcontrol: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/apache/trafficcontrol.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-f2wr-c4c4-xjg7 (GitHub-reviewed advisory GHSA-f2wr-c4c4-xjg7 lists affected ranges: Go github.com/apache/trafficcontrol >=2.0.0-RC0 =2.1.0-RC0 =0 =1.1.4 =0.0.0 <1.1.4-0.20170531185407-738c10fa1b58)

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