CVE-2021-31920

Public Exploit

Description

Istio before 1.8.6 and 1.9.x before 1.9.5 has a remotely exploitable vulnerability where an HTTP request path with multiple slashes or escaped slash characters (%2F or %5C) could potentially bypass an Istio authorization policy when path based authorization rules are used.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Vendor Advisory istio.io
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://istio.io/latest/news/security/istio-security-2021-005/ exploit vendor advisory

Frequently Asked Questions

What is the severity of CVE-2021-31920?
CVE-2021-31920 has been scored as a medium severity vulnerability.
How to fix CVE-2021-31920?
To fix CVE-2021-31920, 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-2021-31920 being actively exploited in the wild?
It is possible that CVE-2021-31920 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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