Insufficient verification of data authenticity in ISC BIND - CVE-2026-19033
Published: September 16, 2026
Vulnerability identifier: #VU150232
CSH Severity: Medium
CVSS v4: 8.3 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N]
CVE-ID: CVE-2026-19033
CWE-ID: CWE-345
Exploitation vector: Remote access
Exploit availability:
No public exploit available
Vulnerability details
The vulnerability allows a remote attacker to add arbitrary data to a zone.
The vulnerability exists due to improper verification of TSIG signatures in named IXFR processing when processing a multi-message TCP IXFR for a TSIG-restricted secondary zone. A remote attacker can send an IXFR transfer without a valid TSIG signature to add arbitrary data to a zone.
Affected software
ISC BIND
Debian Linux
bind9 (Debian package)
Debian Linux
bind9 (Debian package)
How to mitigate CVE-2026-19033
Install security update from vendor's website.
ISC BIND - addressed in versions 9.20.29, 9.20.29-s1, 9.21.26
bind9 (Debian package) - update to 1:9.20.29-1~deb13u1
bind9 (Debian package) - update to 1:9.20.29-1~deb13u1