CVE Intelligence
Medium

CVE-2026-102585 — Moodle: group validation missing when enrolling user to course

A flaw was found in Moodle. When enrolling a user into a course while assigning them to a group, the application does not verify whether the selected group actually belongs to that course. An authenticated user with teacher privileges could exploit this flaw to add users to groups within courses they do not have authorization to access.

Published Sep 30, 2026 · Updated Oct 16, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: fedora

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.2% (30-day exploitation probability)+1
  • Technical severity (medium)+3

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.2%
ahead of 9% of scored CVEs · Oct 15, 2026
Affects
Moodle
Moodle
CVSS base
4.3
Medium · 2 source(s)

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
None
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — git.moodle.org (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Moodle Moodle).
  2. Apply the fixed version or the patch documented under Remediation.
  3. Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Moodle Moodle ≥ 5.1.0 and < 5.1.6≥ 5.2.0 and < 5.2.2 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Network
Attack complexity
Low
Privileges required
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
Low
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
4.3 CVSS 3.1 Medium 2.8 1.4 patrick@puiterwijk.org via NIST National Vulnerability Database
4.3 CVSS 3.1 Medium — — fedora via CVE Program (cve.org) e CISA ADP
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N (score shown at the top: patrick@puiterwijk.org)

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-842

Other CVEs with this weakness →

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
web/proxy/WAF logsnetwork IDS/IPS

Timeline

What happened to this CVE, newest first.

  • 2026
  • SSVC assessment updated
    Oct 16, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 15, 2026
  • Fix documented
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVSS changed · 4.3
    Oct 15, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 15, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 15, 2026 · NIST National Vulnerability Database
  • CVE published
    Sep 30, 2026 · fedora

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

4 on the record

Elsewhere on this site

Moodle
every CVE for this vendor
CWE-842
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-102588 Moodle: csrf in xml grade import 16d
  • CVE-2026-102587 Moodle: user list filters bypass profile field visibility 16d
  • CVE-2026-102582 Moodle: manual enrolment page accessible when plugin disabled 16d
  • CVE-2026-102583 Moodle: incorrect capability check in ai generate image web service 16d
  • CVE-2026-102581 Moodle: xss in forum post templates due to insufficient escaping 16d
  • CVE-2026-102580 Moodle: arbitrary class instantiation via report builder audience classname 16d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-102585 is "Moodle: group validation missing when enrolling user to course", rated Medium. It affects Moodle (Moodle); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 4.3 describes technical severity. EPSS 0.20% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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