CyberSecBulletin
CVE-2026-15689NVD status: Deferred

Dancer2::Plugin::Auth::Extensible: Weak Password Recovery Mechanism for Forgotten Password

Published Updated By the CyberSecBulletin desk

CVE-2026-15689 is a critical-severity weak password recovery mechanism for forgotten password vulnerability in Dancer2::Plugin::Auth::Extensible from ABEVERLEY, with a CVSS 3.1 base score of 9.8 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected Dancer2::Plugin::Auth::Extensible versions: 0.713 and earlier. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 0.6% chance of exploitation within 30 days, which is low compared with other CVEs.

Patch this week

Critical severity: a successful attack would have severe impact.

What to do

  1. Check which version of Dancer2::Plugin::Auth::Extensible you run against the affected versions below, and install the vendor's latest release.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
ABEVERLEYDancer2::Plugin::Auth::Extensible0.713 and earlierNot stated

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H. Scored by CISA (ADP).

Official description

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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Weak Password Recovery Mechanism for Forgotten Password

The product contains a mechanism for users to recover or change their passwords without knowing the original password, but the mechanism is weak.

How developers prevent this class of flaw

  • Make sure that all input supplied by the user to the password recovery mechanism is thoroughly filtered and validated.
  • Do not use standard weak security questions and use several security questions.
  • Make sure that there is throttling on the number of incorrect answers to a security question. Disable the password recovery functionality after a certain (small) number of incorrect guesses.

More Weak Password Recovery Mechanism for Forgotten Password vulnerabilities (CWE-640)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: total).
  3. Record last changed materially (score, affected products, status or references).

References

Recent Weak Password Recovery Mechanism for Forgotten Password vulnerabilities

Spotted an error? Tell us.