Quick answers
- Is This vulnerability exploited in the wild?
- No. Junglewise Threat Intelligence has no report of This vulnerability being exploited in the wild.
- How severe is This vulnerability?
- Medium severity, with a CVSS score of 4, published 18 October 2026.
- Which products and versions are affected?
- Beau Gunderson Ip-Address <= 10.7.3; Beaugunderson Ip-Address <= 10.7.3; ip-address (npm) <= 10.7.3, SEMVER:introduced=0,last_affected=10.7.3.
- Is there a fix for This vulnerability?
- Yes: fixed in 10.7.4. Until then: Reject candidate IP addresses longer than 64 characters before passing them to the parser. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is This vulnerability attacked?
- It is attacked over the network, in a software library.
- Am I affected?
- Check whether you run Beau Gunderson Ip-Address, Beaugunderson Ip-Address or ip-address (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
How to fix
- Fixed in: 10.7.4
Reject candidate IP addresses longer than 64 characters before passing them to the parser.
Technical details
The Address6 constructor uses a regex pattern (/%.*$/) to strip zone identifiers that exhibits quadratic time complexity when processing input containing many % characters followed by a line terminator. Each % character triggers a new regex match attempt, with backtracking proportional to the remaining string length, resulting in O(N²) behavior. An attacker can stall the synchronous parsing with a single request containing 100,000 characters in under 4 seconds of blocking CPU time.
Affected products
- beaugunderson ip-address <= 10.7.3
Timeline
- 2026-10-11: disclosed
- 2026-10-11: patched: fixed in version 10.7.4
- 2026-10-18: advisory