CVE-2021-41088

Remote code execution via the web UI backend of Elvish

Description

Elvish is a programming language and interactive shell, combined into one package. In versions prior to 0.14.0 Elvish's web UI backend (started by `elvish -web`) hosts an endpoint that allows executing the code sent from the web UI. The backend does not check the origin of requests correctly. As a result, if the user has the web UI backend open and visits a compromised or malicious website, the website can send arbitrary code to the endpoint in localhost. All Elvish releases from 0.14.0 onward no longer include the the web UI, although it is still possible for the user to build a version from source that includes the web UI. The issue can be patched for previous versions by removing the web UI (found in web, pkg/web or pkg/prog/web, depending on the exact version).

Categories

8.0
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.24%
Third-Party Advisory github.com Third-Party Advisory github.com
Affected: elves elvish
Published at:
Updated at:

References

Link Tags
https://github.com/elves/elvish/security/advisories/GHSA-fpv6-f8jw-rc3r third party advisory
https://github.com/elves/elvish/commit/ccc2750037bbbfafe9c1b7a78eadd3bd16e81fe5 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-41088?
CVE-2021-41088 has been scored as a high severity vulnerability.
How to fix CVE-2021-41088?
To fix CVE-2021-41088, 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-2021-41088 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-41088 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-41088?
CVE-2021-41088 affects elves elvish.
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