Vulnerability in Abeverley Dancer2::plugin::auth::extensible

CVE-2026-15689

Dancer2::Plugin::Auth::Extensible versions through 0.713 for Perl allow password reset link poisoning via the request Host header in _default_email_password_reset and _default_welcome_send. Both default emails emit a link of the form `$base/login/$code`, whose authority comes from the request Host header, or from X-Forwarded-Host under behind_proxy (obtained from Dancer2's request->base function). A POST to /login carrying submit_reset and a username needs no authentication: it stores a fresh reset code against that account and mails the account holder a link to a host of the sender's choosing. The welcome mail takes the same path when the application calls create_user with email_welcome set. Through 0.711 the handlers read `request->uri_base` and `request->base` directly; Versions 0.712 and later provide an uri_base configuration key that defaults to the untrusted `request->uri_base` when unset. The default configuration with reset_password_handler enabled and the default message text, a recipient who follows the link hands a working reset code to the sender's host, which is enough to take over the account.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.008 (56.1th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 56th percentile — 56.1% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2026-15689: held from 0.006 to 0.008.

EPSS over last 30 days · oldest: 0.006 · newest: 0.008 · change: +0.002

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-15689?
CVE-2026-15689 is a critical-severity vulnerability in Abeverley Dancer2::plugin::auth::extensible, classified under Weak Password Recovery Mechanism for Forgotten Password. CVSS score: 9.8/10. Published 2026-08-15.
How severe is CVE-2026-15689?
Critical severity. CVSS v3 base score is 9.8 out of 10.