Medium severity · published May 27, 2021
CVE-2021-31920
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…
6.5
CVSS
1.3%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.3% · higher than 71% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IS
Istio · Istio
before 1.8.6; 1.9.0 before 1.9.5 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-31920
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-31920
Exploit
https://istio.io/latest/news/security/istio-security-2021-005/
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