CVE-2026-55841highCWE-138

CVE-2026-55841: falha de alta gravidade em graylog2-server

Graylog: Fortigate syslog message parser can be exploited to modify or delete fields from the original message

Publicada em · Atualizada em

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21Vexday Risk Score

Sem sinal de exploração. Nenhum artefato público de exploração conhecido até agora.

ssvc Trackcvss 7.5epss 0.6%
Graylog is a free and open log management platform. Prior to Graylog Server versions 6.3.12, 7.0.7, and 7.1.2 and Graylog Forwarder version 7.3, the FortiGate key-value syslog parser in graylog2-server/src/main/java/org/graylog2/inputs/codecs/GLFortiGateSyslogEvent.java and graylog2-server/src/main/java/org/graylog2/inputs/codecs/SyslogCodec.java mishandles field-like text inside quoted values. GLFortiGateSyslogEvent.getFields() uses KV_PATTERN and QUOTED_KV_PATTERN, while SyslogCodec.parse() invokes the FortiGateSyslogEvent parser; crafted values containing = or backslash-escaped quotes can cause embedded keys such as srcip, dstip, date, time, and tz to remove or overwrite original top-level fields or produce an invalid message that Graylog discards. An unauthenticated network sender who can submit syslog messages can therefore manipulate security-log fields or evade logging to obscure malicious activity. This issue is fixed in Graylog Server versions 6.3.12, 7.0.7, and 7.1.2 and Graylog Forwarder version 7.3.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Produtos afetados
Graylog2 · graylog2-server
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