nanog mailing list archives
Re: RPKI unknown for superprefixes of existing ROA ?
From: Rubens Kuhl <rubensk () gmail com>
Date: Sun, 22 Oct 2023 18:17:42 +0200
On Sun, Oct 22, 2023 at 5:47 PM Job Snijders via NANOG <nanog () nanog org> wrote:
On Sun, 22 Oct 2023 at 17:42, Amir Herzberg <amir.lists () gmail com> wrote:Bill, thanks! You explained the issue much better than me. Yes, the problem is that, in my example, the operator was allocated 1.2.4/22 but the attacker is announcing 1.2.0/20, which is larger than the allocation, so the operator cannot issue ROA for it (or covering it). Of course, the RIR _could_ do it (but I don't think they do, right?). So this `superprefix hijack' may succeed in spite of all the ROAs that the operator could publish. I'm not saying this is much of a concern, as I never heard of such attacks in the wild, but I guess it _could_ happen in the future.How is “success” measured here? The attacker won’t be drawing traffic towards itself destined for addresses in the /22, because of LPM https://en.wikipedia.org/wiki/Longest_prefix_match Attackers don’t hijack IP traffic by announcing less-specifics. It don’t work that way.
Even for positive ROAs (not AS 0 ROAs), that depends on how much of a region's routers have full-routes or use partial routes. In Brazil there are still many Mikrotik devices being used by BGP-speaking networks that fumble on full-routes, and the offending announcement might not have a LPM to choose from. That might be yet more prevalent in routers connecting to IXPs, because even default-route networks would see those announcements without a LPM to follow. Rubens
Current thread:
- Re: RPKI unknown for superprefixes of existing ROA ?, (continued)
- Re: RPKI unknown for superprefixes of existing ROA ? Amir Herzberg (Oct 22)
- Re: RPKI unknown for superprefixes of existing ROA ? Tom Beecher (Oct 22)
- Re: RPKI unknown for superprefixes of existing ROA ? Job Snijders via NANOG (Oct 22)
- Re: RPKI unknown for superprefixes of existing ROA ? Owen DeLong via NANOG (Oct 24)
- Re: RPKI unknown for superprefixes of existing ROA ? Job Snijders via NANOG (Oct 24)
- Re: RPKI unknown for superprefixes of existing ROA ? Randy Bush (Oct 24)
- Re: RPKI unknown for superprefixes of existing ROA ? Owen DeLong via NANOG (Oct 25)
- Re: RPKI unknown for superprefixes of existing ROA ? Owen DeLong via NANOG (Oct 24)
- Re: RPKI unknown for superprefixes of existing ROA ? Tom Beecher (Oct 24)
- Re: RPKI unknown for superprefixes of existing ROA ? Job Snijders via NANOG (Oct 22)
- Re: RPKI unknown for superprefixes of existing ROA ? Rubens Kuhl (Oct 22)
- Re: RPKI unknown for superprefixes of existing ROA ? Owen DeLong via NANOG (Oct 22)
- Re: RPKI unknown for superprefixes of existing ROA ? Job Snijders via NANOG (Oct 22)