CVE-2026-28681: Internet Routing Registry daemon version 4 is an IRR database server, processing IRR objects in the RPSL format.

Internet Routing Registry daemon version 4 is an IRR database server, processing IRR objects in the RPSL format.

Internet Routing Registry daemon version 4 is an IRR database server, processing IRR objects in the RPSL format. From version 4.4.0 to before version 4.4.5 and from version 4.5.0 to before version 4.5.1, an attacker can manipulate the HTTP Host header on a password reset or account creation request. The confirmation link in the resulting email can then point to an attacker-controlled domain. Opening the link in the email is sufficient to pass the token to the attacker, who can then use it on the real IRRD instance to take over the account. A compromised account can then be used to modify RPSL objects maintained by the account's mntners and perform other account actions. If the user had two-factor authentication configured, which is required for users with override access, an attacker is not able to log in, even after successfully resetting the password. This issue has been patched in versions 4.4.5 and 4.5.1.

Description from the National Vulnerability Database, published by GitHub

What it means for a small business

If your business uses irrd, install the vendor's update. If you're not sure whether you use it, ask whoever manages your computers.

How likely is an attack? The Exploit Prediction Scoring System, run by FIRST (the global association of security response teams), puts the odds of this one being exploited in the next 30 days at 0.44%, higher than 38% of CVEs. That’s low, but low isn’t zero, and the odds jump the day someone publishes an exploit. Scored October 28, 2026, updated daily.

Check your own setup

Website check: reads what your site runs from the outside (WordPress version, plugins it can see, old server software) and matches it against this database.
Server check: what your web server says about itself, and whether that version has known flaws.

Sources

Part of the Huttenlocher Technologies vulnerability database, refreshed twice a day from CISA and the NVD. The title, category and plain-language guidance are ours; check the linked record before acting on a detail. This is general guidance, not a review of your systems.

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