CVE-2026-75514
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.
Does this matter?
Lower severity and a low EPSS score (0.46%). Track it; it rarely justifies an emergency change on its own.
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.
- CVSS 3.1
- 5.9 MEDIUMCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
- EPSS
- 0.46% probability · 39th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-350
- Source
- security-advisories@github.com
References
- https://github.com/bunkerity/bunkerweb/commit/1a97e5b3f977130a1b84507a9e1f703c8eec12eb
- https://github.com/bunkerity/bunkerweb/pull/3710
- https://github.com/bunkerity/bunkerweb/releases/tag/v1.6.13
- https://github.com/bunkerity/bunkerweb/security/advisories/GHSA-q54j-5484-pvjm
- https://github.com/bunkerity/bunkerweb/security/advisories/GHSA-q54j-5484-pvjm
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.