symfony/ux-toolkit: Path Traversal Allows Arbitrary File Write and Read via Crafted Recipe Manifest

Exploitation

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

CVSS

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

EPSS

• CVE-2026-55878: 0.19% estimated exploitation activity in the next 30 days; percentile 8.96 (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.

Description The ux:install console command installs files from a recipe kit by copying paths listed in a copy-files map. The only guard against malicious paths was Path::isRelative(), which returns true for paths like ../../../etc. Path::join() then resolves the .. segments without complaint, so the final path can escape the intended directory entirely. A crafted or compromised kit can therefore write attacker-controlled content to arbitrary locations on the developer's machine or CI runner. Because the copy operation creates missing parent directories and can overwrite existing files silently (with --force or in non-interactive environments), an attacker who controls a kit can overwrite files such as controllers, git hooks, or .env to achieve code execution. The source side of copy-files is symmetrically affected, enabling local file reads outside the recipe directory. Resolution The fix introduces an Assert::pathDoesNotEscapeDirectory() helper that rejects any copy-files source or…

Published by the source

19 Jun 2026, 21:42 UTC

Last modified by the source

19 Jun 2026, 21:42 UTC

Source last checked

26 Oct 2026, 14:49 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-p9xj-fpr2-jf2q

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# Patch Next advisory brief: CVE-2026-55878

Advisory: symfony/ux-toolkit: Path Traversal Allows Arbitrary File Write and Read via Crafted Recipe Manifest
IDs: CVE-2026-55878, GHSA-p9xj-fpr2-jf2q
Record: https://patchnext.com/advisories/cve-2026-55878 (revision 1, source checked 26 Oct 2026, 14:49 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.8)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: symfony/ux-toolkit 3.2.0, 2.36.1. A vendor fix does not mean a deployment is fixed.

## Affected components
- Packagist symfony/ux-toolkit: affected >= 2.32.0, < 2.36.1; >= 3.0.0, < 3.2.0; fixed in 2.36.1, 3.2.0

## Suggested inspection (read-only)
- Packagist symfony/ux-toolkit: 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 symfony/ux-toolkit.
- 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-p9xj-fpr2-jf2q (GitHub-reviewed advisory GHSA-p9xj-fpr2-jf2q lists affected ranges: Packagist symfony/ux-toolkit >=2.32.0 =3.0.0 <3.2.0)

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