CVE-2021-42697

Public Exploit

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.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 80.20% Top 5%
Vendor Advisory akka.io Vendor Advisory akka.io Vendor Advisory akka.io Vendor Advisory akka.io
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://akka.io/blog/ vendor advisory
https://doc.akka.io/docs/akka-http/current/security/2021-CVE-2021-42697-stack-overflow-parsing-user-agent.html vendor advisory
https://akka.io/blog/news/2021/11/02/akka-http-10.2.7-released release notes vendor advisory
https://akka.io/blog/news/2021/11/22/akka-http-10.1.15-released release notes vendor advisory
http://packetstormsecurity.com/files/167018/Akka-HTTP-10.1.14-Denial-Of-Service.html third party advisory vdb entry exploit

Frequently Asked Questions

What is the severity of CVE-2021-42697?
CVE-2021-42697 has been scored as a high severity vulnerability.
How to fix CVE-2021-42697?
To fix CVE-2021-42697, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-42697 being actively exploited in the wild?
It is possible that CVE-2021-42697 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~80% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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