# CVE-2021-35250: Directory Transversal Vulnerability in Serv-U 15.3

- Exploited (CISA KEV): no
- Published: 2022-04-25
- CVSS: 7.5 HIGH (v3.1)
- EPSS: 12.8% (96th percentile)
- CWE: CWE-22

A researcher reported a Directory Transversal Vulnerability in Serv-U 15.3. This may allow access to files relating to the Serv-U installation and server files. This issue has been resolved in Serv-U 15.3 Hotfix 1.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Before feed history | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | Before feed history | — | — |
| Fastly | Before feed history | — | — |
| F5 | Rule published | 2024-05-21 | 757 |
| Akamai | No public source | — | — |
| OWASP CRS | Before feed history | — | — |

### F5

- 2024-05-21 · new · rule 200007063
  > Added: signature 200007063 "SolarWinds Serv-U Directory Traversal" (Path Traversal, risk High), systems: Other Web Server. References: CVE-2021-35250.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog

## Our test (measured)

- OWASP Core Rule Set 4.25.0, paranoia level 1, anomaly threshold 5, default CRS settings: blocked (1 of 1 requests blocked), template CVE-2021-35250, 2026-11-02
- OWASP Core Rule Set 4.25.0, paranoia level 2, anomaly threshold 5, default CRS settings: blocked (1 of 1 requests blocked), template CVE-2021-35250, 2026-11-02

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2021-35250 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2021-35250