Linux syslog: Detect suspicious BIND/named error messages

Alerts on Linux syslog messages with BIND named fatal or denied DNS error strings.

FreeReviewedSigma · High · v3
Product
linux
Service
syslog
Author
Florian Roth (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2018-02-20
Updated
2026-07-31
title: "Linux syslog: Detect suspicious BIND/named error messages"
id: a34c0ce4-6d3d-4465-981e-e5e2b710169d
status: test
description: This rule matches specific error strings in Linux syslog associated with BIND/named, including fatal-exit indications and denied or dropped packet conditions. Such messages can reflect probing or exploitation attempts that trigger unexpected server behavior or access denials (for example, attempting restricted DNS operations). It relies on syslog text containing the configured keyword phrases from the named service.
references:
  - https://github.com/ossec/ossec-hids/blob/1ecffb1b884607cb12e619f9ab3c04f530801083/etc/rules/named_rules.xml
  - https://github.com/SigmaHQ/sigma/blob/master/rules/linux/builtin/syslog/lnx_syslog_susp_named.yml
author: Florian Roth (Nextron Systems), Huntrule Team
date: 2018-02-20
modified: 2022-10-05
tags:
  - attack.initial-access
  - attack.t1190
logsource:
  product: linux
  service: syslog
detection:
  keywords:
    - " dropping source port zero packet from "
    - " denied AXFR from "
    - " exiting (due to fatal error)"
  condition: keywords
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: c8e35e96-19ce-4f16-aeb6-fd5588dc5365
    type: derived