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CVE-2026-19033

Unauthenticated IXFR deltas are applied to the live zone before TSIG verification

Published
Last modified
published
Not listed in CISA KEV
Fix
Fix or patch referenced
None on Exploit-DB, Metasploit or GitHub
  • Exploitation: none
  • Automatable: no
  • Technical impact: partial

Summary

For a secondary zone with transfers restricted by TSIG, `named` may start to serve the data provided in a zone transfer before the final message with the TSIG signature arrives. This could allow an attacker that does not actually possess a valid TSIG signature to send unauthorized zone contents to a secondary server. Although no TSIG signature ever arrives, `named` does not rollback to the pre-transfer state. To exploit the vulnerability, the transfer must be a multi-message TCP IXFR, as described by RFC 8945. This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.11.3-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-S1.

Timeline

  1. CVE published
  2. CISA SSVC assessment

    Exploitation: none · Automatable: no · Technical impact: partial

  3. Record last updated

Affected versions

  • ISC BIND 9

    From 9.11.0 · through 9.18.50; From 9.20.0 · through 9.20.27; From 9.21.0 · through 9.21.25; From 9.11.3-S1 · through 9.18.50-S1; From 9.20.9-S1 · through 9.20.27-S1

References 3

kb.isc.org

downloads.isc.org