Zeek: Security Vulnerabilities
Zeek before 8.0.9 contains an uncontrolled memory consumption vulnerability in the FTP analyzer that allows unauthenticated remote attackers to cause process termination by sending a crafted FTP control session negotiating AUTH GSSAPI followed by a large ADAT control line. Attackers can exploit the NVT_Analyzer component's lack of a maximum line length check, causing it to continuously double its internal buffer without bounds during base64 decoding of an attacker-controlled ADAT token, resulting in denial of service of the Zeek sensor.
CVSS Score
8.7
EPSS Score
0.004
Published
2026-07-09
Zeek before 8.0.9 contains a null pointer dereference vulnerability in its Kerberos protocol analyzer that allows unauthenticated remote attackers to crash the sensor by sending a crafted KRB_ERROR message with error-code 25 (KDC_ERR_PREAUTH_REQUIRED) containing a PA-DATA element with padata-type 2, 3, 11, or 19. Attackers can exploit a parser and analyzer state mismatch where proc_padata() dereferences an uninitialized pa_data_element field selected by the wrong parsing arm, triggering a crash via a single UDP or TCP packet to port 88 without any credentials or prior authentication.
CVSS Score
8.7
EPSS Score
0.005
Published
2026-07-09
An issue was discovered in zeek version 4.1.0. There is a HTTP request splitting vulnerability that will invalidate any ZEEK HTTP based security analysis. NOTE: the vendor's position is that the observed behavior is intended
CVSS Score
7.5
EPSS Score
0.009
Published
2021-09-29
In Zeek Network Security Monitor (formerly known as Bro) before 2.6.2, a NULL pointer dereference in the Kerberos (aka KRB) protocol parser leads to DoS because a case-type index is mishandled.
CVSS Score
7.5
EPSS Score
0.014
Published
2019-07-17