CVE-2021-24857
CVSS v3
9.8
CRITICAL
EPSS Score
1.8 %
exploit probability, as of 2026-09-25
CISA KEV
No
known exploited
Exploitation
—
SSVC status
Description
The ToTop Link WordPress plugin through 1.7.1 passes base64 encoded user input to the unserialize() PHP function, which could lead to PHP Object injection if a plugin installed on the blog has a suitable gadget chain.
Technical details
- Published
- 2021-12-13
Frequently asked questions
What is CVE-2021-24857?
The ToTop Link WordPress plugin through 1.7.1 passes base64 encoded user input to the unserialize() PHP function, which could lead to PHP Object injection if a plugin installed on the blog has a suitable gadget chain.
Is CVE-2021-24857 actively exploited?
Active exploitation of CVE-2021-24857 has not been confirmed. Its EPSS score was 1.8% on 2026-09-25, the estimated probability of exploitation in the next 30 days.
What is the CVSS score for CVE-2021-24857?
CVE-2021-24857 has a CVSS v3 base score of 9.8 (CRITICAL severity).
Is CVE-2021-24857 affecting your environment?
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