HOMEVULNERABILITIESCVE-2021-27811
HIGH

CVE-2021-27811

CWE-94Published: May 21, 2021· Updated: Jun 17, 2026

7.2
CVSS v3.1

Official Description

A code injection vulnerability has been discovered in the Upgrade function of QibosoftX1 v1.0. An attacker is able execute arbitrary PHP code via exploitation of client_upgrade_edition.php and Upgrade.php.

NVD Source

Technical Analysis

CVE-2021-27811 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

Exploitation requires high 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 7.2.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityLow
Privileges Req.High
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H

Affected Vendors & Products

qibosoft1 product(s)
qibosoft
Source: NVD CPE · 1 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

ADVISORYhttps://github.com/whiskey-jj/w2s2x2222.github.io/issues/2
ADVISORYhttps://www.cnvd.org.cn/flaw/show/2297879
ADVISORYhttps://github.com/whiskey-jj/w2s2x2222.github.io/issues/2
ADVISORYhttps://www.cnvd.org.cn/flaw/show/2297879

All References (4)

→
https://github.com/whiskey-jj/w2s2x2222.github.io/issues/2Exploit · Issue Tracking · Third Party Advisory
→
https://www.cnvd.org.cn/flaw/show/2297879Third Party Advisory
→
https://github.com/whiskey-jj/w2s2x2222.github.io/issues/2Exploit · Issue Tracking · Third Party Advisory
→
https://www.cnvd.org.cn/flaw/show/2297879Third Party Advisory

Quick Facts

CVE IDCVE-2021-27811
CVSS Score7.2 / 10
SeverityHIGH
WeaknessCWE-94
CISA KEVNo
Affected1 vendor(s)
PublishedMay 21, 2021

Related CVEs (CWE-94)

CVE-2008-0075
10.0
CVE-2009-0208
10.0
CVE-2007-5331
10.0
CVE-2008-0235
10.0
CVE-2007-0065
10.0
CVE-2008-2041
10.0

Recommended Actions

  • →Apply vendor patches immediately
  • →Monitor CVE-2021-27811 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. CVE data is provided under the NVD usage policy.
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