CVE-2021-24927 json
My Calendar < 3.2.18 - Subscriber+ Reflected Cross-Site Scripting
published 2021-11-29 4 y ago modified 2026-06-17 4 mo ago also EUVD-2021-11839
- cvss
- 5.4
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.6%
- EPSS 0.6% chance of exploitation in 30 days, percentile 49%
- public exploits
- 0
- none known
Summary
The My Calendar WordPress plugin before 3.2.18 does not sanitise and escape the callback parameter of the mc_post_lookup AJAX action (available to any authenticated user) before outputting it back in the response, leading to a Reflected Cross-Site Scripting issue
Patch / fix
- my_calendar_project my_calendar 3.2.18
Exploit prediction
0.62% chance of exploitation in the next 30 days, higher than 49% of all scored CVEs (FIRST EPSS, 2026-11-08).
Exploits and checks
- wpscan.com https://wpscan.com/vulnerability/86f3acc7-8902-4215-bd75-6105d601524e referenced PoC, tagged "exploit" by a source, unverified
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 5.4 | CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 3.5 | AV:N/AC:M/Au:S/C:N/I:P/A:N |
Affected products
- Unknown My Calendar
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
- Technology feeds
References
-
wpscan.com
/vulnerability/86f3acc7-8902-4215-bd75-6105d601524e
exploit, third-party-advisory
Sources
- CVE List CVE-2021-24927
- NVD CVE-2021-24927
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