Vulnerability Name:

CVE-2021-20185 (CCN-195790)

Assigned:2020-12-17
Published:2021-01-25
Updated:2022-10-21
Summary:It was found in Moodle before version 3.10.1, 3.9.4, 3.8.7 and 3.5.16 that messaging did not impose a character limit when sending messages, which could result in client-side (browser) denial of service for users receiving very large messages.
CVSS v3 Severity:5.3 Medium (CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
4.6 Medium (Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Low
5.3 Medium (CCN CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
4.6 Medium (CCN Temporal CVSS v3.1 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/E:U/RL:O/RC:C)
Exploitability Metrics:Attack Vector (AV): Network
Attack Complexity (AC): Low
Privileges Required (PR): None
User Interaction (UI): None
Scope:Scope (S): Unchanged
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Low
CVSS v2 Severity:5.0 Medium (CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Authentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
5.0 Medium (CCN CVSS v2 Vector: AV:N/AC:L/Au:N/C:N/I:N/A:P)
Exploitability Metrics:Access Vector (AV): Network
Access Complexity (AC): Low
Athentication (Au): None
Impact Metrics:Confidentiality (C): None
Integrity (I): None
Availibility (A): Partial
Vulnerability Type:CWE-770
Vulnerability Consequences:Denial of Service
References:Source: MITRE
Type: CNA
CVE-2021-20185

Source: XF
Type: UNKNOWN
moodle-cve202120185-dos(195790)

Source: CCN
Type: Moodle Security Advisory MSA-21-0003
Client side denial of service via personal message

Source: MISC
Type: Patch, Vendor Advisory
https://moodle.org/mod/forum/discuss.php?d=417168

Source: CCN
Type: WhiteSource Vulnerability Database
CVE-2021-20185

Vulnerable Configuration:Configuration 1:
  • cpe:/a:moodle:moodle:*:*:*:*:*:*:*:* (Version >= 3.8.0 and < 3.8.7)
  • OR cpe:/a:moodle:moodle:*:*:*:*:*:*:*:* (Version >= 3.9.0 and < 3.9.4)
  • OR cpe:/a:moodle:moodle:*:*:*:*:*:*:*:* (Version >= 3.5.0 and < 3.5.16)
  • OR cpe:/a:moodle:moodle:3.10.0:*:*:*:*:*:*:*

  • Configuration CCN 1:
  • cpe:/a:moodle:moodle:3.5.0:*:*:*:*:*:*:*
  • OR cpe:/a:moodle:moodle:3.10:*:*:*:*:*:*:*
  • OR cpe:/a:moodle:moodle:3.9.3:*:*:*:*:*:*:*
  • OR cpe:/a:moodle:moodle:3.8.6:*:*:*:*:*:*:*
  • OR cpe:/a:moodle:moodle:3.5.15:*:*:*:*:*:*:*

  • * Denotes that component is vulnerable
    BACK
    moodle moodle *
    moodle moodle *
    moodle moodle *
    moodle moodle 3.10.0
    moodle moodle 3.5.0
    moodle moodle 3.10
    moodle moodle 3.9.3
    moodle moodle 3.8.6
    moodle moodle 3.5.15