CVE-2019-15226

Description

Upon receiving each incoming request header data, Envoy will iterate over existing request headers to verify that the total size of the headers stays below a maximum limit. The implementation in versions 1.10.0 through 1.11.1 for HTTP/1.x traffic and all versions of Envoy for HTTP/2 traffic had O(n^2) performance characteristics. A remote attacker may craft a request that stays below the maximum request header size but consists of many thousands of small headers to consume CPU and result in a denial-of-service attack.

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 13.10% Top 10%
Third-Party Advisory github.com Third-Party Advisory github.com Third-Party Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/envoyproxy/envoy/commits/master third party advisory
https://github.com/envoyproxy/envoy/commit/afc39bea36fd436e54262f150c009e8d72db5014 third party advisory patch
https://github.com/envoyproxy/envoy/issues/8520 third party advisory

Frequently Asked Questions

What is the severity of CVE-2019-15226?
CVE-2019-15226 has been scored as a high severity vulnerability.
How to fix CVE-2019-15226?
To fix CVE-2019-15226, 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-2019-15226 being actively exploited in the wild?
It is possible that CVE-2019-15226 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~13% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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