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 the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (8.8): severity, escalated by confirmed exploitation. This CVE's 8.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 8.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-31). FIRST's exploitation probability, not an EchelonGraph model.
- Confirmed exploitation
- None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
- EG Priority
- SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).
Upgrade to Catalyst-Seal 0.03 or later (from the CVE record's solution, CPAN Security Group). Apply it within your standard update timelines.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table
BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.
The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it