Description
A denial-of-service vulnerability was identified in Moodle’s TeX formula editor. When rendering TeX content using mimetex, insufficient execution time limits could allow specially crafted formulas to consume excessive server resources. An authenticated user could abuse this behavior to degrade performance or cause service interruption.
Published: 2026-02-21
Score: 6.5 Medium
EPSS: < 1% Very Low
KEV: No
Impact: Denial of Service
Action: Apply Patch
AI Analysis

Impact

The vulnerability resides in Moodle’s TeX formula editor. When a user renders TeX content using the mimetex engine, the system does not enforce strict execution time limits. An attacker can supply specially crafted formulas that consume an excessive amount of CPU and memory, ultimately exhausting server resources and halting normal operation. This flaw permits a logged‑in user to degrade performance or to trigger a service outage, effectively achieving a denial‑of‑service condition. The weakness reflects uncontrolled resource consumption (CWE‑400) and excessive allocation of resources (CWE‑770).

Affected Systems

The affected product is Moodle, as indicated by the CPE string and the vendor/product naming. The description does not specify particular release numbers, so all publicly available Moodle versions that include the TeX formula editor are potentially impacted. Administrators should verify which Moodle release they run and compare it against the vendor’s security advisories for patches.

Risk and Exploitability

The CVSS score of 6.5 denotes a moderate severity vulnerability. The EPSS score of less than 1% indicates that exploitation is currently considered unlikely, yet the vulnerability is exploitable by any authenticated user. Attackers would need an active session with write permissions to the TeX editor and would craft a formula designed to flood CPU or memory. No proof‑of‑concept code is publicly available, and the issue has not been listed in CISA’s KEV catalog, suggesting no widespread, actively exploited weaponization to date. Nevertheless, administrators should treat this as a risk for service continuity.

Generated by OpenCVE AI on April 17, 2026 at 16:52 UTC.

Remediation

No vendor fix or workaround currently provided.

OpenCVE Recommended Actions

  • Apply the latest Moodle security patch or upgrade to a secure release that addresses the TeX rendering resource limits.
  • Configure the mimetex engine or TeX rendering subsystem to enforce strict execution time and memory limits, such as setting maximum CPU time or memory usage thresholds.
  • Restrict TeX editor access so that only trusted or administrative users can create formulas, reducing the attack surface for unprivileged users.

Generated by OpenCVE AI on April 17, 2026 at 16:52 UTC.

Tracking

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Advisories
Source ID Title
Github GHSA Github GHSA GHSA-cg8j-5cr2-568q Moodle TeX formula editor is vulnerable to DoS through lack of execution time limits
History

Thu, 26 Feb 2026 20:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-770
CPEs cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*

Mon, 23 Feb 2026 20:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'partial'}, 'version': '2.0.3'}


Mon, 23 Feb 2026 15:00:00 +0000

Type Values Removed Values Added
First Time appeared Moodle
Moodle moodle
Vendors & Products Moodle
Moodle moodle

Sat, 21 Feb 2026 06:00:00 +0000

Type Values Removed Values Added
Description A denial-of-service vulnerability was identified in Moodle’s TeX formula editor. When rendering TeX content using mimetex, insufficient execution time limits could allow specially crafted formulas to consume excessive server resources. An authenticated user could abuse this behavior to degrade performance or cause service interruption.
Title Moodle: moodle: uncontrolled resource consumption in tex formula editor leading to denial of service
Weaknesses CWE-400
References
Metrics cvssV3_1

{'score': 6.5, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H'}


cve-icon MITRE

Status: PUBLISHED

Assigner: fedora

Published:

Updated: 2026-02-23T19:30:25.686Z

Reserved: 2026-02-10T13:30:03.986Z

Link: CVE-2026-26047

cve-icon Vulnrichment

Updated: 2026-02-23T19:30:17.476Z

cve-icon NVD

Status : Analyzed

Published: 2026-02-21T06:17:00.377

Modified: 2026-02-26T19:45:29.417

Link: CVE-2026-26047

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-04-17T17:00:10Z

Weaknesses