CVE-2021-42697
HIGH7.5EPSS 75.5%Uncontrolled Recursion in Akka HTTP
Published: 5/24/2022Modified: 9/30/2025
Description
Akka HTTP 10.1.x 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.
Affected packages (7)
- Maven/com.typesafe.akka:aakka-http-core_2.13.0-M3>= 10.1.0
- Maven/com.typesafe.akka:akka-http-core_2.11>= 10.1.0, < 10.1.15
- Maven/com.typesafe.akka:akka-http-core_2.12>= 10.1.0, < 10.1.15
- Maven/com.typesafe.akka:akka-http-core_2.13>= 10.1.0, < 10.1.15
- Maven/com.typesafe.akka:akka-http-core_2.13.0-M5>= 10.1.0
- Maven/com.typesafe.akka:akka-http-core_2.13.0-RC2>= 10.1.0
- Maven/com.typesafe.akka:akka-http-core_2.13.0-RC3>= 10.1.0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH7.5 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H |
References (8)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2021-42697
- PATCHhttps://github.com/akka/akka-http
- WEBhttp://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html
- WEBhttps://akka.io/blog
- WEBhttps://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released
- WEBhttps://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released
- WEBhttps://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html
- WEBhttps://github.com/akka/akka-http/pull/3924