MEDIUM
CVE-2021-20801
CWE-611Published: October 13, 2021· Updated: Jun 17, 2026
6.5
CVSS v3.1
Official Description
Cybozu Remote Service 3.1.8 to 3.1.9 allows a remote authenticated attacker to conduct XML External Entity (XXE) attacks and obtain the information stored in the product via unspecified vectors. This issue occurs only when using Mozilla Firefox.
Technical Analysis
CVE-2021-20801 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
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), with a CVSS base score of 6.5.
CVSS v3.1 Vector Breakdown
Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.Low
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityNone
AvailabilityNone
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
Affected Vendors & Products
cybozu1 product(s)
remote service manager
Source: NVD CPE · 2 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://jvn.jp/en/jp/JVN52694228/index.htmlThird Party Advisory
→
https://kb.cybozu.support/article/37423Vendor Advisory
→
https://jvn.jp/en/jp/JVN52694228/index.htmlThird Party Advisory
→
https://kb.cybozu.support/article/37423Vendor Advisory
Quick Facts
CVE IDCVE-2021-20801
CVSS Score6.5 / 10
SeverityMEDIUM
WeaknessCWE-611
CISA KEVNo
Affected1 vendor(s)
PublishedOct 13, 2021
Related CVEs (CWE-611)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2021-20801 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.