8.8High

CVE-2026-85491

Catalyst::Seal versions before 0.03 for Perl allow one request to disable a path or route a later one past an authorization check via a dispatch memo keyed on the request path alone. Catalyst::Seal replaces the dispatcher's prepare_action with a version that memoises how a path resolved: which dispatch type matched, at which level, and what was left over as arguments. The key is the request path and nothing else. Action roles that match on the method, content type, scheme or query make that resolution depend on state the key does not carry, so the memo answers for a request it was not built from. A path that resolves to no action is memoised as well, and replaying that entry returns without consulting any dispatch type, so no action is set and the request fails. A GET of a path whose action is declared POST-only therefore disables that path for every later request, the correct POST included. An entry that did resolve replays the level the earlier descent reached. Where a POST-only action sits below a shallower action on the same path, a GET memoises the shallow route, and a later POST is dispatched there with an auto() guarding the deeper controller never running. The memo is cleared only when an action is registered, which happens at setup, so an entry lasts for the life of the process, and its cap of 2048 entries bounds how many paths one caller can disable. In the configuration measured, the misroute lands on the less privileged action, so it is an authorization check not running rather than a privilege gain.

What this means for your business

  • An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 0.4% chance of attack attempts being seen in the next 30 days, ranking above 25% of all known flaws.

What to do

  1. 1Ask your IT team or provider whether any of your systems use the affected product.
  2. 2If you do, follow the vendor's guidance. No patch reference has been published yet.

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Scoring

CVSS
8.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-706
Assigned by
9b29abf9-4ab0-4765-b253-1875cd9b441e

Dates

Published
2026-09-24
Last modified
2026-09-25
Sources
NVD

References