CVE-2026-26047 | Moodle: moodle: uncontrolled resource consumption in tex formula editor leading to denial of service

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 Last update: 2026-06-17 Assigner: [email protected] Source: [email protected]
NVD Status：Analyzed，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2026-26047 is rated Low Risk (38.5/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.43%). Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-26047

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.06% 0.43% +0.38%
2 2026-02-21 — 0.06% —

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-26047

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]

Weakness enumeration for CVE-2026-26047

GitHub Security Advisory for CVE-2026-26047

GHSA-cg8j-5cr2-568q · Severity: medium · Ecosystem: composer — Moodle TeX formula editor is vulnerable to DoS through lack of execution time limits

OS Trackers for CVE-2026-26047

vendor priority summary link
ubuntu medium CVE-2026-26047 medium priority: Ubuntu including 1 source packages (moodle), 6 status rows across 6 suites (bionic, jammy, noble, questing, upstream, xenial): DNE 3, needs-triage 3. https://ubuntu.com/security/CVE-2026-26047

Affected software / configurations for CVE-2026-26047

Vendor Product Version Raw CPE
moodle moodle < 4.5.9 cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
moodle moodle >= 5.0.0, < 5.0.5 cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
moodle moodle >= 5.1.0, < 5.1.2 cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*

References for CVE-2026-26047

cvelogic Threat Intelligence