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Fencer Vulns
medium 6.5

CVE-2026-26047 json

Moodle: moodle: uncontrolled resource consumption in tex formula editor leading to denial of service

published 2026-02-21 8 mo ago modified 2026-09-08 2 mo ago also BIT-moodle-2026-26047 , EUVD-2026-7527 , GHSA-cg8j-5cr2-568q

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.5%
EPSS 0.5% chance of exploitation in 30 days, percentile 43%
public exploits
0
none known

Summary

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.

Patch / fix

  • packagist moodle/moodle 4.5.9, 5.0.5, 5.1.2
  • bitnami moodle 4.5.9, 5.0.5, 5.1.2
  • moodle moodle 4.5.9, 5.0.5, 5.1.2

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-26047 updated cvss 6.5

moodle: Moodle: Uncontrolled Resource Consumption in TeX Formula Editor Leading to Denial of Service

  • Red Hat All currently supported Red Hat products
    not affected: vulnerable code not present

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
8 mo ago

Exploit prediction

0.51% chance of exploitation in the next 30 days, higher than 43% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
GitHub 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
OSV 3.1 6.5 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Affected packages

ecosystem package affected fixed in
packagist moodle/moodle
>=5.1.0-beta, <5.1.2
>=5.0.0-beta, <5.0.5
<4.5.9
5.1.2
5.0.5
4.5.9
bitnami moodle
<4.5.9
>=5.0.0, <5.0.5
>=5.1.0, <5.1.2
4.5.9
5.0.5
5.1.2

Classification

Weakness
  • CWE-400 Uncontrolled Resource Consumption
  • CWE-770 Allocation of Resources Without Limits or Throttling

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.