Vulnerability in Hahwul Dalfox

CVE-2026-45090

Dalfox is a powerful open-source XSS scanner and utility focused on automation. Prior to 2.13.0, ParameterAnalysis in pkg/scanning/parameterAnalysis.go runs two sequential worker stages that both write to the same results channel. The channel is correctly closed after the first stage completes (close(results) at line 438), but the second stage — which processes POST-body parameters (dp) — is then launched with the same already-closed channel as its output. When a scanned parameter is reflected, processParams executes results <- paramResult on the closed channel, triggering a Go runtime panic that crashes the entire dalfox process. In server mode, the crash is remotely triggerable by any unauthenticated caller who can reach the REST API, because the default configuration has no API key and the second stage activates whenever options.Data != "" (i.e., the attacker supplies the data field) and the target reflects at least one parameter. This vulnerability is fixed in 2.13.0.

Vulnerability class: Race Condition

EPSS: 0.002 (13.8th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-45090?
CVE-2026-45090 is a high-severity vulnerability in Hahwul Dalfox, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 7.5/10. Published 2026-05-27.
How severe is CVE-2026-45090?
High severity. CVSS v3 base score is 7.5 out of 10.