Fix SSRF scan failing open on malformed punycode hostnames - #704
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Fix SSRF scan failing open on malformed punycode hostnames#704MaiDormo wants to merge 2 commits into
MaiDormo wants to merge 2 commits into
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get_hostname_options() decoded xn-- hostnames with IDNA without guarding the call. A malformed punycode label (e.g. xn--a.attacker.com) raised UnicodeError, which propagated through find_hostname_in_context() and was swallowed by the catch-all in run_vulnerability_scan(), so the SSRF scan failed open. Fall back to the raw hostname when decoding fails.
Only affects Python 3.8
timokoessler
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Aug 22, 2026
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get_hostname_options()decodesxn--hostnames with IDNA without guarding the call. A malformed punycode label (for examplexn--a.attacker.com, valid at DNS level under an attacker-owned domain) raisesUnicodeError, which propagates throughfind_hostname_in_context()and gets swallowed by the catch-all inrun_vulnerability_scan(). The SSRF scan therefore fails open and requests to private IPs go through unblocked.This PR wraps the decode in
try/except UnicodeErrorand falls back to the raw hostname, so the scan still runs against the requested host.Changes:
Related: #703