CVE-2021-27933
CVE-2021-27933 is a medium-severity vulnerability in Pfsense with a CVSS 3.x base score of 6.1. Its EPSS exploit-prediction score of 27% places it in the 98th percentile, indicating an elevated likelihood of exploitation. 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: 27% (98th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-79
- Affected product: Pfsense
- Published:
- Last modified:
Description
pfSense 2.5.0 allows XSS via the services_wol_edit.php Description field.
Frequently asked questions
- What is CVE-2021-27933?
- pfSense 2.5.0 allows XSS via the services_wol_edit.php Description field.
- How severe is CVE-2021-27933?
- CVE-2021-27933 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-2021-27933 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 27% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-27933?
- CVE-2021-27933 affects Pfsense. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2021-27933?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-27933 published?
- CVE-2021-27933 was published on 2021-04-28 and last updated on 2026-06-17.
References
Affected products (1)
- cpe:2.3:a:pfsense:pfsense:2.5.0:*:*:*:*:*:*:*
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