CVE-2026-93710: Dancer2 versions from 2.0.0 before 2.2.0 for Perl dispatch a route that a dying hook refused when the exception handler halts the response in compile_hooks
Stig Palmquist 22 Sep 2026 00:55 UTC
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CVE-2026-93710 CPAN Security Group
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CVE ID: CVE-2026-93710
Distribution: Dancer2
Versions: from 2.0.0 before 2.2.0
MetaCPAN: https://metacpan.org/dist/Dancer2
VCS Repo: https://github.com/PerlDancer/Dancer2
Dancer2 versions from 2.0.0 before 2.2.0 for Perl dispatch a route that
a dying hook refused when the exception handler halts the response in
compile_hooks
Description
-----------
Dancer2 versions from 2.0.0 before 2.2.0 for Perl dispatch a route that
a dying hook refused when the exception handler halts the response in
compile_hooks.
A hook that dies fires core.app.hook_exception, then calls cleanup
unless the failing hook is the exception handler. A handler that halts
does not stop that cleanup, which discards the request, response and
session the dispatcher has yet to read, so the refused route runs.
The handler has to halt the response object by calling its halt method
or setting is_halted: the halt keyword unwinds through with_return
before cleanup runs.
A check in a before hook is not enforced: the caller gets the refusal,
while the route body runs and its writes land.
Problem types
-------------
- CWE-460 Improper Cleanup on Thrown Exception
Solutions
---------
Upgrade to Dancer2 2.2.0 or later.
References
----------
https://github.com/PerlDancer/Dancer2/security/advisories/GHSA-v527-r4px-7vx7
https://github.com/PerlDancer/Dancer2/commit/8fd31a32798f9aa25e4fccbd6c7cb9dd3a0c1029.patch
https://metacpan.org/release/CROMEDOME/Dancer2-2.2.0/changes
Timeline
--------
- 2026-09-16: Version 2.2.0 released with fix.