CVE Intelligence
Medium Cross-site scripting

CVE-2025-67849 — Moodle: moodle: cross-site scripting (xss) via improper sanitization of ai prompt responses

A flaw was found in Moodle. This cross-site scripting (XSS) vulnerability, caused by improper sanitization of AI prompt responses, allows attackers to inject malicious HTML or script into web pages. When other users view these compromised pages, their sessions could be stolen, or the user interface could be manipulated.

Published Feb 3, 2026 · Updated Oct 13, 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 0.3% (30-day exploitation probability)+3
  • 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
0.27%
ahead of 18% of scored CVEs · Oct 14, 2026
Affects
Moodle
Moodle
CVSS base
6.1
Medium · 3 source(s)
Prioritization reference: 7.3 provisional

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
Total
partial · total control of the vulnerable component

Remediation

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

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

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. The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
  3. No fix documented in the sources: reduce exposure and monitor the vendor advisory.
  4. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  5. Search available logs for exploit probes matching the vulnerability class (cross-site scripting), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Moodle Moodle ≥ 4.5.0 and < 4.5.8≥ 5.0.0 and < 5.0.4version 5.1.0 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
None
User interaction
Required
Scope
Changed
Confidentiality
Low
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
7.3 CVSS 3.1 High 2.1 5.2 patrick@puiterwijk.org via NIST National Vulnerability Database
7.3 CVSS 3.1 High — — fedora via CVE Program (cve.org) e CISA ADP
6.1 CVSS 3.1 Medium 2.8 2.7 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 7.3 (patrick@puiterwijk.org via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-79 · Cross-site Scripting (XSS)

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.27%

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).
  • Monitor CSP violation reports and script payloads in reflected parameters.
web/proxy/WAF logsnetwork IDS/IPSapplication logs

Timeline

What happened to this CVE, newest first.

  • 2026
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • CVSS changed · 6.1
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Analyzed
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Feb 3, 2026 · fedora

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

2 on the record

Elsewhere on this site

Moodle
every CVE for this vendor
CWE-79
other pages naming this weakness

Related CVEs (same products)

  • Medium CVE-2022-50943 Moodle LMS 4.0 Cross-Site Scripting via course search.php May 10, 2026
  • High CVE-2026-26046 Moodle: moodle: improper input sanitization in tex filter administration setting Feb 21, 2026
  • Medium CVE-2026-26047 Moodle: moodle: uncontrolled resource consumption in tex formula editor leading to denial of service Feb 21, 2026
  • High CVE-2026-26045 Moodle: moodle: improper validation in file restore functionality leading to remote code execution Feb 21, 2026
  • Medium CVE-2025-67857 Moodle: moodle: data exposure of user identifiers in urls Feb 3, 2026
  • High CVE-2025-67851 Moodle: moodle: formula injection allows arbitrary formula execution via unescaped data export Feb 3, 2026

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 fixed version, patch or mitigation documented.
  • 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-2025-67849 is "Moodle: moodle: cross-site scripting (xss) via improper sanitization of ai prompt responses", 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 6.1 describes technical severity. EPSS 0.27% 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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