Medium severity · published Jan 26, 2023
CVE-2021-36539
Instructure Canvas LMS didn't properly deny access to locked/unpublished files when the unprivileged user access the DocViewer based file preview URL (canvadoc_session_url)
6.5
CVSS
0.9%
EPSS
No
On KEV
Description
Instructure Canvas LMS didn't properly deny access to locked/unpublished files when the unprivileged user access the DocViewer based file preview URL (canvadoc_session_url).
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.9% · higher than 59% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
CL
Canvas Learning Management Service · Instructure
before 2022-10-15 · source: NVD
Affected product
CL
Canvas Learning Management Service
Instructure
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-36539
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-36539
Exploit
https://github.com/gaukas/instructure-canvas-file-oracle
Exploit
https://github.com/instructure/canvas-lms/issues/1905
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