dssrf: every IPv6 category bypasses is_url_safe

A vulnerability on dssrf allow, an attacker to use, one of them following ipv6 ```rust Input Category http://[::1]/ IPv6 loopback http://[fc00::1]/ IPv6 ULA http://[fe80::1]/ IPv6 link-local http://[::ffff:127.0.0.1]/ IPv4-mapped loopback http://[::ffff:169.254.169.254]/ IPv4-mapped IMDS http://[::ffff:100.64.0.1]/ IPv4-mapped CGNAT http://[64:ff9b::7f00:1]/ NAT64 well-known prefix http://[64:ff9b:1::1]/ NAT64 local-use (RFC 8215) http://[5f00::1]/ SRv6 SID (RFC 9602) http://[3fff::1]/ IPv6 documentation (RFC 9637) http://[fec0::1]/ IPv6 site-local (deprecated, RFC 3879) http://[::127.0.0.1]/ IPv4-compatible IPv6 ``` one of those to bypass dssrf and the attacker get **SSRF**, we claim that ipv6 disabled entirely that is wrong on our documentation ### POC ```bash mkdir dssrf-poc && cd dssrf-poc npm init -y >/dev/null npm install dssrf@^1.0.2 cat > audit.js <<'EOF' const dssrf = require('dssrf'); const cases = [ ['http://[::1]/', 'IPv6 loopback'], ['http://[fc00::1]/', 'IPv6 ULA'], ['http://[fe80::1]/', 'IPv6 link-local'], ['http://[::ffff:127.0.0.1]/', 'IPv4-mapped loopback'], ['http://[::ffff:169.254.169.254]/', 'IPv4-mapped IMDS'], ['http://[64:ff9b::7f00:1]/', 'NAT64 well-known + 127.0.0.1'], ['http://[64:ff9b:1::1]/', 'NAT64 local-use (RFC 8215)'], ['http://[5f00::1]/', 'SRv6 SID (RFC 9602)'], ['http://[fec0::1]/', 'IPv6 site-local deprecated'], ['http://127.0.0.1/', 'IPv4 loopback (control)'], ['http://10.0.0.1/', 'IPv4 RFC1918 (control)'], ['http://8.8.8.8/', 'PUBLIC IPv4 (control)'], ]; (async () => { for (const [url, label] of cases) { const safe = await dssrf.is_url_safe(url); console.log(`${safe ? '✓ALLOW' : '·block'} ${url.padEnd(40)} ${label}`); } })(); EOF node audit.js ``` ### Credit Million Thank's to <[email protected]> for reporting that responsibly. ### Update Users need to update from now to dssrf 1.0.3 ### Lessons Learned AS we see in the past and today, a lot of advisories or cves bypasses uses IPv6, and IPv6 is the weakest link to be configured correctly and rarely properly tested, Since we blocked ipv4, our ipv6 blocking logic completly broken and never works

Source published

6 May 2026 18:13:32 UTC

Source modified

18 Jun 2026 23:00:08 UTC

Observed here

24 Oct 2026 13:17:17 UTC

Source terms

GitHub Advisory Database · CC-BY-4.0

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This view projects the publisher's source fields for reading; the original JSON retains additional fields and CVE enrichment containers. Attribution: osv · GitHub Advisory Database · CC-BY-4.0. Source text is retained; field grouping and change labels are provided by ChangeIntel.

CVSS_V4 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

Publisher rating · HIGH