CVE-2026-31283

Unrestricted Password Reset Causing Email Bombing in Totara LMS

Published Apr 13, 2026 CVSS 3.1 · 9.8 Critical EPSS < 1% KEV · Not listed
Description
In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email address. which can be used for an Email Bombing attack. NOTE: the Supplier's position is that the pwresettime configuration defaults to 30 minutes, the pwresettime configuration is a hard control enforced via flag PWRESET_STATUS_ALREADYSENT, and no further password-reset email messages are sent if this flag is active for a specific email address.

Analysis

AI-generated

Technical impact

The flaw resides in the forgot password API of Totara Learning Management System (LMS) releases 19.1.5 and earlier, where no rate limiting is applied to the target email address. An attacker can trigger an arbitrary number of password‑reset emails to a chosen account, overwhelming the mailbox and disrupting legitimate use. The vendor states that the pwresettime configuration defaults to 30 minutes and that a hard‑control flag ("PWRESET_STATUS_ALREADYSENT") blocks additional reset emails once it is active for a specific address, yet documented behavior still permits rapid successive requests before the flag is set.

Affected Systems

Totara Learning Management System versions 19.1.5 and earlier are affected; no other vendor or product variants are listed.

Risk and Exploitability

The CVSS base score of 9.8 indicates a very high severity, and the EPSS score of less than 1 % suggests the current exploitation likelihood is low. This vulnerability is not listed in CISA’s KEV catalog. The likely attack vector is the publicly exposed, unauthenticated API endpoint that accepts any email address; an attacker can directly target any account without prior credentials.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Apply an official Totara LMS patch that implements rate limiting on the forgot password endpoint; upgrades newer than 19.1.5 are recommended.
  • If an immediate upgrade is not possible, place external rate‑limiting or firewall rules on the forgot password URL to constrain the number of requests per address within a given time frame.
  • Continuously monitor request logs for spikes in the forgot password endpoint and deploy automated alerts or temporary blocks against abusive traffic.

Generated by OpenCVE AI on April 29, 2026 at 01:56 UTC.

Tracking

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Advisories

No advisories available
History
Type Values Removed Values Added
Title Unrestricted Password Reset Causing Email Bombing in Totara LMS
Type Values Removed Values Added
Description In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email address. which can be used for an Email Bombing attack. In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email address. which can be used for an Email Bombing attack. NOTE: the Supplier's position is that the pwresettime configuration defaults to 30 minutes, the pwresettime configuration is a hard control enforced via flag PWRESET_STATUS_ALREADYSENT, and no further password-reset email messages are sent if this flag is active for a specific email address.
Type Values Removed Values Added
Title Missing Rate Limiting on Totara LMS Forgot Password API Allows Email Bombing
Type Values Removed Values Added
Metrics cvssV3_1

{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}

ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}

Type Values Removed Values Added
Title Missing Rate Limiting on Totara LMS Forgot Password API Allows Email Bombing
Weaknesses CWE-770
Type Values Removed Values Added
First Time appeared Totara
Totara lms
Vendors & Products Totara
Totara lms
Type Values Removed Values Added
Description In Totara LMS v19.1.5 and before, the forgot password API does not implement rate limiting for the target email address. which can be used for an Email Bombing attack.
References
Weaknesses
  • CWE-770

    Allocation of Resources Without Limits or Throttling

Sources

Status
PUBLISHED
Assigner
mitre
Published
Updated
Apr 24, 2026, 7:32 AM
Reserved
Mar 9, 2026, 12:00 AM
Status
Deferred
Published
Apr 13, 2026, 3:17 PM
Modified
Jun 17, 2026, 10:33 AM