mise HTTP backend uses raw version path for install symlink destination

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

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

EPSS

• CVE-2026-54557: 0.18% estimated exploitation activity in the next 30 days; percentile 7.98 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary The mise HTTP backend builds its install symlink destination from the raw resolved version string for non-latest versions. Normal tool install paths use the sanitized version pathname, but the HTTP backend's symlink path uses the raw value. On Unix-like systems, if that version is an absolute path, PathBuf::join discards the intended mise installs root. A repository-controlled .tool-versions file can therefore make mise install create a symlink outside the mise install tree. With binpath, the same issue can place an executable symlink under an attacker-selected absolute prefix, such as a developer-tool prefix that is later added to PATH. The reproducer below also models a CI/developer workflow where a later step executes a preexisting trusted command from a user-local PATH prefix. The absolute-version HTTP entry replaces that command with a symlink to downloaded HTTP content. A non-absolute version control does not replace the trusted PATH command. Affected Code In…

Published by the source

23 Jun 2026, 18:13 UTC

Last modified by the source

21 Jul 2026, 15:04 UTC

Source last checked

26 Oct 2026, 15:43 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-f94h-j2qg-fxw3

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# Patch Next advisory brief: CVE-2026-54557

Advisory: mise HTTP backend uses raw version path for install symlink destination
IDs: CVE-2026-54557, GHSA-f94h-j2qg-fxw3
Record: https://patchnext.com/advisories/cve-2026-54557 (revision 1, source checked 26 Oct 2026, 15:43 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: mise 2026.6.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io mise: affected <= 2026.5.16; fixed in 2026.6.1

## Suggested inspection (read-only)
- crates.io mise: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on mise.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-f94h-j2qg-fxw3 (GitHub-reviewed advisory GHSA-f94h-j2qg-fxw3 lists affected ranges: crates.io mise >=0 <=2026.5.16)

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