CVE-2021-27811
CVSS v3
7.2
HIGH
EPSS Score
1.2 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
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.
Technical details
- Published
- 2021-05-21
Frequently asked questions
What is CVE-2021-27811?
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.
Is CVE-2021-27811 actively exploited?
Active exploitation of CVE-2021-27811 has not been confirmed. Its EPSS score was 1.2% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-27811?
CVE-2021-27811 has a CVSS v3 base score of 7.2 (HIGH severity).
Is CVE-2021-27811 affecting your environment?
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