CVE-2021-43795

Name: CVE-2021-43795
Creator: NVD / NIST
Published: 2021-12-02T18:15:08.267+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.64%

Last modified Jun 17, 2026

CVE-2021-43795 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. Armeria is an open source microservice framework. In affected versions an attacker can access an Armeria server's local file system beyond its restricted directory by sending an HTTP request whose path contains `%2F` (encoded `/`), such as `/files/..%2Fsecrets.txt`, bypassing Armeria's path validation logic. EPSS estimates a 1.64% chance of exploitation in the next 30 days.

Description

Armeria is an open source microservice framework. In affected versions an attacker can access an Armeria server's local file system beyond its restricted directory by sending an HTTP request whose path contains `%2F` (encoded `/`), such as `/files/..%2Fsecrets.txt`, bypassing Armeria's path validation logic. Armeria 1.13.4 or above contains the hardened path validation logic that handles `%2F` properly. This vulnerability can be worked around by inserting a decorator that performs an additional validation on the request path.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

1.64%

73.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

Affected Software

Vendor	Product	Versions
Linecorp	Armeria	< 1.13.4

References

https://github.com/line/armeria/commit/e2697a575e9df6692b423e02d731f293c1313284Patch, Third Party Advisory
https://github.com/line/armeria/pull/3855Third Party Advisory
https://github.com/line/armeria/security/advisories/GHSA-8fp4-rp6c-5gcvThird Party Advisory
https://github.com/line/armeria/commit/e2697a575e9df6692b423e02d731f293c1313284Patch, Third Party Advisory
https://github.com/line/armeria/pull/3855Third Party Advisory
https://github.com/line/armeria/security/advisories/GHSA-8fp4-rp6c-5gcvThird Party Advisory

Timeline

Published: Dec 2, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-43795?

How severe is CVE-2021-43795?

CVE-2021-43795 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.64% probability of exploitation in the next 30 days.

How do I fix CVE-2021-43795?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-43795?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST