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Vulnerability details: VCID-3b5u-7ww6-xydm
Vulnerability ID VCID-3b5u-7ww6-xydm
Aliases CVE-2021-20183
GHSA-xhfx-rm8q-c3xv
Summary Moodle Vulnerable to Reflected Cross-site Scripting It was found in Moodle before version 4.0.0-beta that some search inputs were vulnerable to reflected Cross-site Scripting (XSS) due to insufficient escaping of search queries.
Status Published
Exploitability 0.5
Weighted Severity 6.2
Risk 3.1
Affected and Fixed Packages Package Details
Weaknesses (3)
CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-1035 OWASP Top Ten 2017 Category A9 - Using Components with Known Vulnerabilities
CWE-937 OWASP Top Ten 2013 Category A9 - Using Components with Known Vulnerabilities
System Score Found at
epss 0.00617 https://api.first.org/data/v1/epss?cve=CVE-2021-20183
epss 0.00617 https://api.first.org/data/v1/epss?cve=CVE-2021-20183
cvssv3.1_qr MODERATE https://github.com/advisories/GHSA-xhfx-rm8q-c3xv
cvssv3.1 5.4 https://github.com/moodle/moodle/commit/dc9de7b0d487b73c23c221dc0b8b6e01654921f3
generic_textual MODERATE https://github.com/moodle/moodle/commit/dc9de7b0d487b73c23c221dc0b8b6e01654921f3
cvssv3.1 5.4 https://moodle.org/mod/forum/discuss.php?d=417166
generic_textual MODERATE https://moodle.org/mod/forum/discuss.php?d=417166
cvssv2 4.3 https://nvd.nist.gov/vuln/detail/CVE-2021-20183
cvssv3.1 5.4 https://nvd.nist.gov/vuln/detail/CVE-2021-20183
generic_textual MODERATE https://nvd.nist.gov/vuln/detail/CVE-2021-20183
Reference id Reference type URL
https://api.first.org/data/v1/epss?cve=CVE-2021-20183
https://github.com/moodle/moodle/commit/dc9de7b0d487b73c23c221dc0b8b6e01654921f3
https://moodle.org/mod/forum/discuss.php?d=417166
https://nvd.nist.gov/vuln/detail/CVE-2021-20183
cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:* https://nvd.nist.gov/vuln/search/results?adv_search=true&isCpeNameSearch=true&query=cpe:2.3:a:moodle:moodle:*:*:*:*:*:*:*:*
GHSA-xhfx-rm8q-c3xv https://github.com/advisories/GHSA-xhfx-rm8q-c3xv
No exploits are available.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N Found at https://github.com/moodle/moodle/commit/dc9de7b0d487b73c23c221dc0b8b6e01654921f3
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N Found at https://moodle.org/mod/forum/discuss.php?d=417166
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Vector: AV:N/AC:M/Au:N/C:N/I:P/A:N Found at https://nvd.nist.gov/vuln/detail/CVE-2021-20183
Exploitability (E) Access Vector (AV) Access Complexity (AC) Authentication (Au) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

high

functional

unproven

proof_of_concept

not_defined

local

adjacent_network

network

high

medium

low

multiple

single

none

none

partial

complete

none

partial

complete

none

partial

complete
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N Found at https://nvd.nist.gov/vuln/detail/CVE-2021-20183
Attack Vector (AV) Attack Complexity (AC) Privileges Required (PR) User Interaction (UI) Scope (S) Confidentiality Impact (C) Integrity Impact (I) Availability Impact (A)

network

adjacent_network

local

physical

low

high

none

low

high

none

required

unchanged

changed

high

low

none

high

low

none

high

low

none
Exploit Prediction Scoring System (EPSS)
Percentile 0.68941
EPSS Score 0.00617
Published At June 30, 2025, 12:55 p.m.
Date Actor Action Source VulnerableCode Version
2025-07-01T12:27:35.788398+00:00 GithubOSV Importer Import https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2022/05/GHSA-xhfx-rm8q-c3xv/GHSA-xhfx-rm8q-c3xv.json 36.1.3