CVE-2026-10822 PUBLISHED

Key Record using PRIVATEDNS algorithm may lead to unexpected exit

Assigner: isc
Reserved: 04.06.2026 Published: 22.07.2026 Updated: 22.07.2026

If BIND encounters a particular invalid data structure in a DNS record, it will accept the invalid data, and may subsequently abort and exit.

BIND will first need to store a DNS record for a key (KEY, DNSKEY, etc.). That key must specify a PRIVATEDNS algorithm (253), and in the algorithm identifier, improperly give a length longer than the actual identifier data. The invalid identifier will be stored. If BIND later needs to render that record to text, it will use the invalid length during processing, leading to a consistency check failing. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.

Metrics

CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS Score: 6.5

Product Status

Vendor ISC
Product BIND 9
Versions Default: unaffected
  • affected from 9.18.0 to 9.18.50 (incl.)
  • affected from 9.20.0 to 9.20.24 (incl.)
  • affected from 9.21.0 to 9.21.23 (incl.)
  • affected from 9.18.11-S1 to 9.18.50-S1 (incl.)
  • affected from 9.20.9-S1 to 9.20.24-S1 (incl.)

Exploits

This flaw was discovered in internal testing. We are not aware of any active exploits.

Workarounds

No workarounds known.

Solutions

Upgrade to the patched release most closely related to your current version of BIND 9: 9.20.26, 9.21.24, or 9.20.26-S1.

References

Problem Types

  • CWE-617 Reachable Assertion CWE
  • CWE-1284 Improper Validation of Specified Quantity in Input CWE

Impacts

  • 9.20 and 9.21 may abort and exit unexpectedly. 9.18 has not actually been confirmed to exhibit the unexpected exit but does share the problem code.