Cyber Resilience

CVE-2026-33702

Access Control in Chamilo Lms ≤ 1.11.38

Published
10 April 2026
Modified
16 April 2026
Patch / advisory
CVSS Score v3.1 7.1
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
EPSS Score 0.0024 15th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2026-33702 is a high-severity Authorization Bypass Through User-Controlled Key (CWE-639) vulnerability in Chamilo Chamilo Lms. Its CVSS base score is 7.1 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 15th 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 AC-3 (Access Enforcement) and AC-6 (Least Privilege) — 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-2026-33702 is an Insecure Direct Object Reference (IDOR) vulnerability, classified under CWE-639, affecting Chamilo LMS, an open-source learning management system. The issue resides in the lp_ajax_save_item.php endpoint used for saving Learning Path progress. In versions prior to 1.11.38 and 2.0.0-RC.3, the endpoint accepts a uid (user ID) parameter directly from $_REQUEST without verifying that it matches the requesting user, allowing unauthorized modification of another user's Learning Path data, including score, status, completion, and time spent. The vulnerability carries a CVSS v3.1 base score of 7.1 (AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L), indicating high integrity impact with low privileges required.

Any authenticated user enrolled in a course can exploit this vulnerability over the network with low complexity and no user interaction. By simply modifying the uid parameter in a request to lp_ajax_save_item.php, an attacker can overwrite the Learning Path progress of any other user in the same course, potentially disrupting educational tracking, falsifying achievements, or enabling academic fraud.

The vulnerability is addressed in Chamilo LMS versions 1.11.38 and 2.0.0-RC.3 through fixes documented in GitHub commits 6331d051b4468deb5830c01d1e047c5e5cf2c74f and bf3f6c6949b5c882b48a9914baa19910417e4551, as detailed in the security advisory GHSA-3rv7-9fhx-j654. Security practitioners should upgrade to these patched versions to mitigate the risk.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Chamilo LMS is a learning management system. Prior to 1.11.38 and 2.0.0-RC.3, Chamilo LMS contains an Insecure Direct Object Reference (IDOR) vulnerability in the Learning Path progress saving endpoint. The file lp_ajax_save_item.php accepts a uid (user ID) parameter directly from…

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$_REQUEST and uses it to load and modify another user's Learning Path progress — including score, status, completion, and time — without verifying that the requesting user matches the target user ID. Any authenticated user enrolled in a course can overwrite another user's Learning Path progress by simply changing the uid parameter in the request. This vulnerability is fixed in 1.11.38 and 2.0.0-RC.3.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise TechniquesAI

T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1565.001 Stored Data Manipulation Impact
Adversaries may insert, delete, or manipulate data at rest in order to influence external outcomes or hide activity, thus threatening the integrity of the data.
Why these techniques?

IDOR in web-based LMS endpoint enables unauthorized stored data modification (T1565.001) and is exploitable via network-accessible web app (T1190).

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

CVEs Like This One

CVE-2026-32930Same product: Chamilo Chamilo Lms
CVE-2026-33736Same product: Chamilo Chamilo Lms
CVE-2026-32894Same product: Chamilo Chamilo Lms
CVE-2026-33703Same product: Chamilo Chamilo Lms
CVE-2026-34602Same product: Chamilo Chamilo Lms
CVE-2026-33141Same product: Chamilo Chamilo Lms
CVE-2026-34370Same product: Chamilo Chamilo Lms
CVE-2026-30881Same product: Chamilo Chamilo Lms
CVE-2024-30616Same product: Chamilo Chamilo Lms
CVE-2025-50187Same product: Chamilo Chamilo Lms

Affected Assets

chamilo
chamilo lms
2.0.0 · ≤ 1.11.38

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • AC-6 Least Privilege
  • SI-10 Information Input Validation
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)

Validate
Prove the fix (OWASP ASVS)

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces approved authorizations to prevent authenticated users from modifying another user's Learning Path progress via the uid parameter.

prevent

Implements least privilege to restrict users to accessing and modifying only their own Learning Path progress data.

prevent

Validates the uid input parameter against the authenticated user's identity to block unauthorized object references.

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.AA-05 full match
prevents

Enforcing authorization policy and least privilege directly blocks user-controlled key tampering that bypasses access checks.

PR.IR-01 mostly match
prevents

Logical access controls prevent unauthorized data access that results from missing authorization checks on object references.

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.

detects

Security testing can detect missing authorization checks but does not prevent the weakness in production.

prevents

Information access restriction explicitly enforces that users may only retrieve data they are authorized to see, directly addressing user-controlled key bypass.

prevents

Access control policy directly requires enforcement of authorization rules that prevent unauthorized access via manipulated keys.

prevents

Managing access rights includes ensuring users can only access their own records and not bypass authorization by altering identifiers.

mitigates

Privileged access rights control restricts what data each user may access, mitigating direct object reference attacks.

prevents

Secure development lifecycle includes authorization design but does not itself implement runtime access checks.

References