CVE-2026-75514 (GCVE-0-2026-75514)
Vulnerability from cvelistv5
Published
2026-08-20 18:31
Modified
2026-08-20 19:00
Severity ?
5.9 (Medium) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CWE
  • CWE-350 - Reliance on Reverse DNS Resolution for a Security-Critical Action
Summary
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.
References
Impacted products
Vendor Product Version
bunkerity bunkerweb Version: < 1.6.13
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