Cyber Resilience

CVE-2026-26045

RCE in Moodle ≤ 4.5.9

Published
21 February 2026
Modified
26 February 2026
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0055 43th percentile
Risk Priority 53 floored blend · peak EPSS

Summary

CVE-2026-26045 is a high-severity Code Injection (CWE-94) vulnerability in Moodle Moodle. Its CVSS base score is 7.2 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 43th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-26045 is a code injection vulnerability (CWE-94) in Moodle's backup restore functionality, published on 2026-02-21. The flaw occurs because specially crafted backup files are not properly validated during processing, potentially leading to unintended execution of server-side code when a malicious backup is restored. It affects Moodle instances where backup restoration is enabled.

Exploitation requires authenticated access with privileged user permissions, as restore capabilities are typically restricted to administrators or similar roles. An attacker with such access could upload and restore a malicious backup file over the network with low complexity and no user interaction, achieving high confidentiality, integrity, and availability impacts. This could result in full compromise of the Moodle server, with a CVSS v3.1 base score of 7.2 (AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H).

Red Hat advisories provide further details on the vulnerability, including mitigation and patching guidance, at https://access.redhat.com/security/cve/CVE-2026-26045, with an associated Bugzilla entry at https://bugzilla.redhat.com/show_bug.cgi?id=2440901.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A flaw was identified in Moodle’s backup restore functionality where specially crafted backup files were not properly validated during processing. If a malicious backup file is restored, it could lead to unintended execution of server-side code. Since restore capabilities are…

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typically available to privileged users, exploitation requires authenticated access. Successful exploitation could result in full compromise of the Moodle server.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
T1059.002 AppleScript Execution
Adversaries may abuse AppleScript for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.005 Visual Basic Execution
Adversaries may abuse Visual Basic (VB) for execution.
T1059.006 Python Execution
Adversaries may abuse Python commands and scripts for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-43425Same product: Moodle Moodle
CVE-2025-3642Same product: Moodle Moodle
CVE-2025-3641Same product: Moodle Moodle
CVE-2024-28593Same product: Moodle Moodle
CVE-2025-67847Same product: Moodle Moodle
CVE-2026-26046Same product: Moodle Moodle
CVE-2023-28333Same product: Moodle Moodle
CVE-2024-43426Same product: Moodle Moodle
CVE-2024-34009Same product: Moodle Moodle
CVE-2023-28330Same product: Moodle Moodle

Affected Assets

moodle
moodle
≤ 4.5.9 · 5.0.0 — 5.0.5 · 5.1.0 — 5.1.2

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)
  • V1.3.1

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation finds code paths that accept and execute externally influenced strings.

Input validation directly stops untrusted data from being used to construct executable code without neutralization.

Least privilege limits the damage an injected code fragment can perform once executed.

Requiring documented secure development standards and tools enforces use of safe code-generation APIs and escaping.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.PS-06 mostly match
prevents

PR.PS-06's SDLC practices directly target injection flaws via secure coding and testing (mostly), yet as a single broad outcome it leaves many code-generation specifics unaddressed (partial).

PR.DS-10 none match
prevents

PR.DS-10 protects runtime data confidentiality/integrity but has no bearing on neutralizing externally influenced input during code generation, so neither direction shows any preventive effect.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

Banning unapproved code samples and unauthenticated web services, combined with secure-coding standards and SAST, prevents the dynamic generation or inclusion of attacker-supplied code.

none

Controls that restrict unauthorized or malicious code from being introduced via external networks or removable media limit opportunities for an attacker to inject and execute arbitrary code.

References