Description

Applications using the “Sensitive Headers” functionality in Spring Cloud Netflix Zuul 2.2.6.RELEASE and below may be vulnerable to bypassing the “Sensitive Headers” restriction when executing requests with specially constructed URLs. Applications that use Spring Security's StrictHttpFirewall (enabled by default for all URLs) are not affected by the vulnerability, as they reject requests that allow bypassing.

Affected Spring Products and Versions

• Spring Cloud Netflix Zuul
  • 2.2.6 and below

Mitigation

Users should upgrade to 2.2.7 and higher. Releases that have fixed this issue include:

• Spring Cloud Netflix Zuul
  • 2.2.7

Credit

This issue was identified and responsibly reported by threedr3am (threedr3am at foxmail.com).

References

• https://docs.spring.io/spring-cloud-netflix/docs/2.2.6.RELEASE/reference/html/#cookies-and-sensitive-headers

History

• 2021-02-11: Initial vulnerability report published.