Drupal Core: Private Files Can Be Cached and Served to Other Users

Published as "Drupal core allows Exploiting Incorrectly Configured Access Control Security Levels"

low Drupal · Last reviewed Nov 8, 2026

CVE: CVE-2025-13083
GHSA: GHSA-mhpg-hpj5-73r2
Packagist: PKSA-d8tb-wwz2-ctxk
Reported: Nov 18, 2025

Can leak private files through Varnish or a CDN on Drupal sites that serve non-public files through a module adding its own file scheme.

Affected and fixed versions

In drupal/core. Find the row for the version you run, and update to the release next to it.

If you run	Update to	Support
11.2.0 – 11.2.7	11.2.8
11.0.0 – 11.1.8	11.1.9
10.5.0 – 10.5.5	10.5.6

Show 2 older branches

8.0.0 – 10.4.8	10.4.9
7.0 – 7.102.x	7.103

Upgrade

Run the line for the branch you are on.

composer require drupal/core:^11.2.8
composer require drupal/core:^11.1.9
composer require drupal/core:^10.5.6

What this means

Drupal can send some non-public files with a Cache-Control: public header, so a shared cache in front of the site keeps a copy. Another visitor can then get that cached file even though they aren't allowed to see it. Drupal's advisory names Varnish and CDNs as examples of such caches.

Who is affected

Only sites that meet both of these conditions:

Non-public files are served through a custom or contributed module that adds its own file scheme, handled by core's system module. Sites that use only core's own private and temporary file handling aren't affected.
A shared cache, such as Varnish or a CDN, sits in front of the site.

The attacker also has to request a file that a user with more access already requested, while it is still in the cache. Drupal rates this as complex and the configuration as uncommon.

What to do

Update to the fixed release for your branch:

Drupal 10.4: update to 10.4.9
Drupal 10.5: update to 10.5.6
Drupal 11.1: update to 11.1.9
Drupal 11.2: update to 11.2.8

Drupal 11.0.x, 10.3.x and older no longer get security fixes, so move to a supported branch.

Reported by Damien McKenna and tame4tex.

Check your app with an agent

Paste this into a coding agent that can read your project, such as Claude Code, Codex or Amp. It checks your composer.lock against the versions above and tells you what to update, without changing anything.

Check whether the PHP project you have access to is affected by this security advisory, and tell me what to update. Do a read-only check: don't edit files, don't run composer update or composer require, and don't try to reproduce the flaw.

Advisory: Drupal Core: Private Files Can Be Cached and Served to Other Users (CVE-2025-13083, GHSA-mhpg-hpj5-73r2)
Details: https://phpnews.net/security/drupal/ghsa-mhpg-hpj5-73r2

Affected versions, as Composer constraints:
- drupal/core: >=7.0,<7.103|>=11.2.0,<11.2.8|>=11.0.0,<11.1.9|>=10.5.0,<10.5.6|>=8.0.0,<10.4.9

Fixed releases:
- 11.2.0 – 11.2.7: update to 11.2.8
- 11.0.0 – 11.1.8: update to 11.1.9
- 10.5.0 – 10.5.5: update to 10.5.6

1. Find every composer.lock in the project outside vendor/ (a monorepo can have one per app) and read the installed version of each package above. Packages installed as dependencies of other packages count too.
2. Compare each installed version with its constraint: "|" separates alternative ranges, and "," means both bounds apply.
3. For each affected install, read "What this means" at https://phpnews.net/security/drupal/ghsa-mhpg-hpj5-73r2 and check whether the project meets the conditions it describes (a feature in use, a config value, a driver). Say which conditions you could check and which you couldn't.
4. Report a table: lock file | package | installed version | affected (yes, no or unknown) | conditions met (yes, no or unknown) | update to | evidence. For each affected package, give the command that would fix it, without running it: composer update <package> --with-dependencies when it is only installed as a dependency of another package, or composer require with the fixed version when composer.json requires it directly. If the installed version is on a branch with no fixed release listed, say it needs a move to a newer branch.

Sources

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