Description
BunkerWeb is an open-source, next-generation Web Application Firewall. Prior to 1.6.13, the blacklist, greylist, and antibot modules in src/common/core/blacklist/blacklist.lua, src/common/core/greylist/greylist.lua, and src/common/core/antibot/antibot.lua trust PTR suffix matches in IGNORE_RDNS, GREYLIST_RDNS, and ANTIBOT_IGNORE_RDNS without using get_ips to confirm that the hostname resolves to the client address. An unauthenticated remote attacker who controls a PTR record can spoof a trusted suffix to bypass rDNS-based blacklisting, gain greylist treatment, or skip an antibot challenge. This issue is fixed in version 1.6.13.
References5
Metrics
- CVSS 3.1
-
5.9
MEDIUM
Score source: CNA
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS — exploit probability
- 1% percentile: 49 · as of 10 November 2026
- CWE
- CWE-350
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