CVE-2021-42078
CVE-2021-42078 is a medium-severity vulnerability in Php Event Calendar Project Php Event Calendar with a CVSS 3.x base score of 6.1. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.
Key facts
- Severity: Medium (CVSS 3.x base score 6.1)
- CVSS v2: 4.3
- EPSS exploit prediction: 1% (54th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Php Event Calendar Project Php Event Calendar
- Published:
- Last modified:
Description
PHP Event Calendar through 2021-11-04 allows persistent cross-site scripting (XSS), as demonstrated by the /server/ajax/events_manager.php title parameter. This can be exploited by an adversary in multiple ways, e.g., to perform actions on the page in the context of other users, or to deface the site.
Frequently asked questions
- What is CVE-2021-42078?
- PHP Event Calendar through 2021-11-04 allows persistent cross-site scripting (XSS), as demonstrated by the /server/ajax/events_manager.php title parameter. This can be exploited by an adversary in multiple ways, e.g., to perform actions on the page in the context of other users, or to deface the site.
- How severe is CVE-2021-42078?
- CVE-2021-42078 has a CVSS 3.x base score of 6.1, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
- Is CVE-2021-42078 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-42078?
- CVE-2021-42078 affects Php Event Calendar Project Php Event Calendar. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-42078?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-42078 published?
- CVE-2021-42078 was published on 2021-11-08 and last updated on 2026-06-17.
References
- http://seclists.org/fulldisclosure/2021/Nov/24
- https://www.syss.de/fileadmin/dokumente/Publikationen/Advisories/SYSS-2021-049.txt
Affected products (1)
- cpe:2.3:a:php_event_calendar_project:php_event_calendar:2021-11-04:*:*:*:lite:*:*:*
Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities
- CVE-2025-49410 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Imran Emu TC…
- CVE-2024-47875 — Critical (CVSS 10.0): DOMPurify is a DOM-only, super-fast, uber-tolerant XSS sanitizer for HTML, MathML and SVG. DOMpurify was vulnerable to…
- CVE-2024-6886 — Critical (CVSS 10.0): Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in Gitea…
- CVE-2023-45144 — Critical (CVSS 10.0): com.xwiki.identity-oauth:identity-oauth-ui is a package to aid in building identity and service providers based on…
- CVE-2023-45138 — Critical (CVSS 10.0): Change Request is an pplication allowing users to request changes on a wiki without publishing the changes directly.…
- CVE-2022-4361 — Critical (CVSS 10.0): Keycloak, an open-source identity and access management solution, has a cross-site scripting (XSS) vulnerability in the…
Browse all CWE-79 (Cross-site Scripting (XSS)) vulnerabilities →