HIGH
CVE-2021-3310
CWE-59Published: March 10, 2021· Updated: Jun 17, 2026
7.8
CVSS v3.1
Official Description
Western Digital My Cloud OS 5 devices before 5.10.122 mishandle Symbolic Link Following on SMB and AFP shares. This can lead to code execution and information disclosure (by reading local files).
Technical Analysis
CVE-2021-3310 requires local access, meaning attackers must already have a foothold on the target system.
Exploitation requires low privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 7.8.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorLocal
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Affected Vendors & Products
westerndigital9 product(s)
my cloud osmy cloud dl2100my cloud dl4100my cloud ex2 ultramy cloud ex2100my cloud ex4100my cloud mirror gen 2my cloud pr2100my cloud pr4100
Source: NVD CPE · 9 total CPE entries
Exploit & PoC Resources
NO KNOWN EXPLOITNo public exploit confirmed at this time
Exploit-DB
Offensive Security exploit database
GitHub PoC Search
Community PoC repositories
Rapid7 / Metasploit
Metasploit module search
PacketStorm
Security advisories & exploits
NVD Detail
Official NIST entry
MITRE CVE
CVE Program entry
External links open in a new tab. Always verify in a controlled environment before use.
Official Patches & Advisories
All References (4)
→
→
https://www.zerodayinitiative.com/advisories/ZDI-21-277/Third Party Advisory
→
→
https://www.zerodayinitiative.com/advisories/ZDI-21-277/Third Party Advisory
Quick Facts
CVE IDCVE-2021-3310
CVSS Score7.8 / 10
SeverityHIGH
WeaknessCWE-59
CISA KEVNo
Affected1 vendor(s)
PublishedMar 10, 2021
Related CVEs (CWE-59)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-3310 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.