CVE-2021-42697

7.5 HIGH

Akka HTTP 10.1.x before 10.1.15 and 10.2.x before 10.2.7 can encounter stack exhaustion while parsing HTTP headers, which allows a remote...

Published: 2021-11-02 · Last updated: 2026-06-17

Severity and scoring

CVSS: 7.5 HIGH
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-674

Affected products

Vendor	Product
akka	http_server

Description

Akka HTTP 10.1.x before 10.1.15 and 10.2.x before 10.2.7 can encounter stack exhaustion while parsing HTTP headers, which allows a remote attacker to conduct a Denial of Service attack by sending a User-Agent header with deeply nested comments.

Source: NVD

References

[NVD]https://nvd.nist.gov/vuln/detail/CVE-2021-42697
[Exploit reference]http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html
[Vendor advisory]https://akka.io/blog/
[Vendor advisory]https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released
[Vendor advisory]https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released
[Vendor advisory]https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html
[Exploit reference]http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html
[Vendor advisory]https://akka.io/blog/
[Vendor advisory]https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released
[Vendor advisory]https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released
[Vendor advisory]https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html

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