Memory exhaustion in http4s-async-http-client with large or malicious compressed responses

Exploitation

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

CVSS

not scored

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

Impact A server we connect to with http4s-async-http-client could theoretically respond with a large or malicious compressed stream and exhaust memory in the client JVM. It does not affect http4s servers, other client backends, or clients that speak only to trusted servers. This is related to a transitive dependency on netty-codec-4.1.45.Final, which is affected by CVE-2020-11612. Patches Upgrade to http4s-async-http-client = 0.21.8. All 1.0 milestones are also safe. Workarounds Add an explicit runtime dependency on async-http-client's netty dependencies that evicts them to an unaffected version: References https://app.snyk.io/vuln/SNYK-JAVA-IONETTY-564897 https://github.com/http4s/http4s/issues/3681 For more information If you have any questions or comments about this advisory: Open an issue in http4s Contact a maintainer privately per http4s' security policy

Published by the source

16 Oct 2020, 17:03 UTC

Last modified by the source

9 Jan 2023, 05:04 UTC

Source last checked

26 Oct 2026, 15:53 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-8hxh-r6f7-jf45

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# Patch Next advisory brief: GHSA-8hxh-r6f7-jf45

Advisory: Memory exhaustion in http4s-async-http-client with large or malicious compressed responses
IDs: GHSA-8hxh-r6f7-jf45
Record: https://patchnext.com/advisories/ghsa-8hxh-r6f7-jf45 (revision 1, source checked 26 Oct 2026, 15:53 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Unrated
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.http4s:http4s-async-http-client_2.12 0.21.8; org.http4s:http4s-async-http-client_2.13 0.21.8. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.http4s:http4s-async-http-client_2.12: affected <= 0.21.7; fixed in 0.21.8
- Maven org.http4s:http4s-async-http-client_2.13: affected <= 0.21.7; fixed in 0.21.8

## Suggested inspection (read-only)
- Maven org.http4s:http4s-async-http-client_2.12: check the installed version with your package manager.
- Maven org.http4s:http4s-async-http-client_2.13: 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 org.http4s:http4s-async-http-client_2.12, org.http4s:http4s-async-http-client_2.13.
- 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-8hxh-r6f7-jf45 (GitHub-reviewed advisory GHSA-8hxh-r6f7-jf45 lists affected ranges: Maven org.http4s:http4s-async-http-client_2.13 >=0 =0 <=0.21.7)

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