CyberSecBulletin
CVE-2026-13410NVD status: Deferred

Dancer::Plugin::Auth::Google: Improper Certificate Validation

CVE-2026-13410 is a high-severity improper certificate validation vulnerability in Dancer::Plugin::Auth::Google from GARU, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 0.08 as the first without the flaw, so updating Dancer::Plugin::Auth::Google to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.38% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update Dancer::Plugin::Auth::Google to 0.08 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
  3. Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.

Affected products and versions

VendorProductAffected versionsFixed in
GARUDancer::Plugin::Auth::Googlebefore 0.080.08

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
HighSuccess depends on conditions outside the attacker's control.
Privileges required
NoneNo account or login is needed.
User interaction
RequiredA user must take an action such as opening a file or link.
Scope
ChangedThe attack can reach beyond the vulnerable component into other systems.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
LowPerformance or availability is reduced.

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

Official description

Dancer::Plugin::Auth::Google versions before 0.08 for Perl have TLS verification disabled. The default user agent is initialised with SSL_verify_mode explicitly disabled. An attacker with network man-in-the-middle (MITM) capability between the Dancer application and googleapis.com can intercept the OAuth2 token exchange and userinfo fetch, return a forged access_token and user profile, and be logged in to the Dancer application as any Google user.

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

The underlying weakness: Improper Certificate Validation

The product does not validate, or incorrectly validates, a certificate.

How developers prevent this class of flaw

  • Certificates should be carefully managed and checked to assure that data are encrypted with the intended owner's public key.
  • If certificate pinning is being used, ensure that all relevant properties of the certificate are fully validated before the certificate is pinned, including the hostname.

More Improper Certificate Validation vulnerabilities (CWE-295)

Timeline

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

References

Recent Improper Certificate Validation vulnerabilities

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