CVE-2019-15226

high-risk
Published 2019-10-09

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.

Do I need to act?

!
17.0% chance of exploitation in next 30 days
EPSS score — higher than 83% of all CVEs
-
Not on CISA KEV list
No confirmed active exploitation reported to CISA
?
Patch status unknown
Check vendor advisories for fix availability and mitigation guidance
7
CVSS 7.5/10 High
NETWORK / LOW complexity

Affected Vendors

57
/ 100
high-risk
Severity 26/34 · High
Exploitability 13/34 · Low
Exposure 18/34 · Moderate