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TI-2021-17930 Aliases CVE-2021-41088GHSA-fpv6-f8jw-rc3r

Remote code execution via the web UI backend of Elvish

Priority LOW 39CWE-668Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
Required
Attack complexity
Low
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and GitHub. Impact type from CWE-346.

Summary

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).

Why it matters now

EPSS 0.00537 45th percentileScored 2026-11-07
Fix Fixed elvish (elves): 0.14.0github.com/elves/elvish (Go): 0.14.0

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
elveselvishbefore 0.14.00.14.0Patch availableCNA
—github.com/elves/elvish (Go)before 0.14.00.14.0Patch availableGHSA-fpv6-f8jw-rc3r
  • elvish Vendorelves Affected before 0.14.0 Fixed in 0.14.0 Patch available CNA
  • github.com/elves/elvish (Go) Vendor— Affected before 0.14.0 Fixed in 0.14.0 Patch available GHSA-fpv6-f8jw-rc3r

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:elv:elvish:*:*:*:*:*:*:*:*before 0.14.0VulnerableElv
  • cpe:2.3:a:elv:elvish:*:*:*:*:*:*:*:* Versions before 0.14.0 Vulnerable ·Elv

Remediation

  • Fix · CNA elvish (elves) Fixed in 0.14.0
  • Fix · GHSA-fpv6-f8jw-rc3r github.com/elves/elvish (Go) Fixed in 0.14.0 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-41088
  2. 2026-10-03 Alias added: GHSA-fpv6-f8jw-rc3r

References

Patch 1

Advisory 2

Other 1

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences