GHSA-xgch-x3mx-cm3cMedium

safeurl is Missing IPv6 CIDR Ranges in Blocklist

Published
July 15, 2026
Last Modified
July 15, 2026

🔗 CVE IDs covered (1)

📋 Description

The privateNetworks blocklist was found to be missing newly added CIDR ranges. More specifically, the following CIDR ranges were not being blocked:

  • 64:ff9b:1::/48: NAT64 local-use prefix (RFC 8215)
  • 5f00::/16: Segment Routing (SRv6) SIDs (RFC 9602)
  • 3fff::/20: documentation prefix (RFC 9637)
  • 100:0:0:1::/64: Dummy IPv6 Prefix (RFC 9780)

Impact

If exploited, an attacker would potentially be able to reach resources hosted on the IPs residing in the missing ranges.

Workarounds

Disable IPv6 by setting EnableIPv6(false). This is the default behavior of the library.

Resolution

Upgrade to v0.2.4

Credits

safeurl thanks @tonghuaroot for reporting.

🎯 Affected products1

  • go/github.com/doyensec/safeurl:< 0.2.4

🔗 References (3)