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TI-2026-05215 Aliases CVE-2026-5946GHSA-cqgq-ff3f-rj7r

Invalid handling of CLASS != IN

Priority MEDIUM 43CWE-125Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
Partial Red Hat: 32 fixed, 1 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-125 and the CVSS impact.

Summary

Multiple flaws have been identified in `named` related to the handling of DNS messages whose CLASS is not Internet (`IN`) — for example, `CHAOS` or `HESIOD`, or DNS messages that specify meta-classes (`ANY` or `NONE`) in the question section. Specially crafted requests reaching the affected code paths — recursion, dynamic updates (`UPDATE`), zone change notifications (`NOTIFY`), or processing of `IN`-specific record types in non-`IN` data — can cause assertion failures in `named`. This issue affects BIND 9 versions 9.11.0 through 9.16.50, 9.18.0 through 9.18.48, 9.20.0 through 9.20.22, 9.21.0 through 9.21.21, 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.48-S1, and 9.20.9-S1 through 9.20.22-S1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01942 80th percentileScored 2026-11-07
Fix Partial Red Hat: 22 advisoriesRed Hat: 32 fixed, 1 without a fix

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
ISCBIND 99.11.0 – 9.16.50; 9.18.0 – 9.18.48; 9.20.0 – 9.20.22; 9.21.0 – 9.21.21; 9.11.3-S1 – 9.16.50-S1; 9.18.11-S1 – 9.18.48-S1; 9.20.9-S1 – 9.20.22-S1—No fix listedCNA
  • BIND 9 VendorISC Affected 9.11.0 – 9.16.50; 9.18.0 – 9.18.48; 9.20.0 – 9.20.22; 9.21.0 – 9.21.21; 9.11.3-S1 – 9.16.50-S1; 9.18.11-S1 – 9.18.48-S1; 9.20.9-S1 – 9.20.22-S1 Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:*9.11.0 – 9.16.50; 9.18.0 to before 9.18.49; 9.20.0 to before 9.20.23; 9.21.0 to before 9.21.22VulnerableISC
  • cpe:2.3:a:isc:bind:*:*:*:*:-:*:*:* Versions 9.11.0 – 9.16.50; 9.18.0 to before 9.18.49; 9.20.0 to before 9.20.23; 9.21.0 to before 9.21.22 Vulnerable ·ISC

Remediation

Red Hat 22 advisories

  • RHSA-2026:95727 Released 2026-11-06 · Red Hat rating Important
    bind security, bug fix, and enhancement update
    • Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION) bind-32:9.8.2-0.68.rc1.el6_10.20, bind-libs-32:9.8.2-0.68.rc1.el6_10.20
    • Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION) bind-sdb-32:9.8.2-0.68.rc1.el6_10.20
  • RHSA-2026:95477 Released 2026-11-05 · Red Hat rating Important
    bind security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream AUS (v.8.4) bind-32:9.11.26-4.el8_4.10, bind-libs-32:9.11.26-4.el8_4.10, bind-libs-lite-32:9.11.26-4.el8_4.10 +5
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4) bind-32:9.11.26-4.el8_4.10, bind-libs-32:9.11.26-4.el8_4.10, bind-libs-lite-32:9.11.26-4.el8_4.10 +5
    • Red Hat Enterprise Linux BaseOS AUS (v.8.4) bind-32:9.11.26-4.el8_4.10, bind-export-libs-32:9.11.26-4.el8_4.10
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4) bind-32:9.11.26-4.el8_4.10, bind-export-libs-32:9.11.26-4.el8_4.10
  • RHSA-2026:95478 Released 2026-11-05 · Red Hat rating Important
    bind security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) bind-32:9.11.36-8.el8_8.11, bind-libs-lite-32:9.11.36-8.el8_8.11, bind-pkcs11-32:9.11.36-8.el8_8.11 +4
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) bind-32:9.11.36-8.el8_8.11, bind-libs-lite-32:9.11.36-8.el8_8.11, bind-pkcs11-32:9.11.36-8.el8_8.11 +4
    • Red Hat Enterprise Linux BaseOS E4S (v.8.8) bind-32:9.11.36-8.el8_8.11, bind-export-libs-32:9.11.36-8.el8_8.11
    • Red Hat Enterprise Linux BaseOS TUS (v.8.8) bind-32:9.11.36-8.el8_8.11, bind-export-libs-32:9.11.36-8.el8_8.11
Show 19 more Red Hat advisories
  • RHSA-2026:95435 Released 2026-11-05 · Red Hat rating Important
    bind security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) bind-32:9.11.36-3.el8_6.13, bind-chroot-32:9.11.36-3.el8_6.13, bind-devel-32:9.11.36-3.el8_6.13 +12
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) bind-32:9.11.36-3.el8_6.13, bind-chroot-32:9.11.36-3.el8_6.13, bind-devel-32:9.11.36-3.el8_6.13 +12
    • Red Hat Enterprise Linux BaseOS AUS (v.8.6) bind-32:9.11.36-3.el8_6.13, bind-export-devel-32:9.11.36-3.el8_6.13, bind-export-libs-32:9.11.36-3.el8_6.13
    • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6) bind-32:9.11.36-3.el8_6.13, bind-export-devel-32:9.11.36-3.el8_6.13, bind-export-libs-32:9.11.36-3.el8_6.13
  • RHSA-2026:95242 Released 2026-11-04 · Red Hat rating Important
    bind security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream E4S (v.9.2) bind-32:9.16.23-11.el9_2.12, bind-dnssec-utils-32:9.16.23-11.el9_2.12, bind-libs-32:9.16.23-11.el9_2.12
  • RHSA-2026:94278 Released 2026-11-03 · Red Hat rating Important
    bind9.18 security, bug fix, and enhancement update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) bind9.18-libs-32:9.18.29-4.el9_6.5
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) bind9.18-32:9.18.29-4.el9_6.5, bind9.18-dnssec-utils-32:9.18.29-4.el9_6.5, bind9.18-libs-32:9.18.29-4.el9_6.5
  • RHSA-2026:94277 Released 2026-11-03 · Red Hat rating Important
    bind9.16 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream AUS (v.8.6) bind9.16-32:9.16.23-0.7.el8_6.12, bind9.16-libs-32:9.16.23-0.7.el8_6.12
    • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) bind9.16-32:9.16.23-0.7.el8_6.12, bind9.16-libs-32:9.16.23-0.7.el8_6.12
  • RHSA-2026:94115 Released 2026-11-03 · Red Hat rating Important
    bind security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream EUS (v. 10.0) bind-32:9.18.33-4.el10_0.6, bind-dnssec-utils-32:9.18.33-4.el10_0.6, bind-libs-32:9.18.33-4.el10_0.6
  • RHSA-2026:79160 Released 2026-10-08 · Red Hat rating Important
    bind9.16 security, bug fix, and enhancement update
    • Red Hat Enterprise Linux AppStream E4S (v.8.8) bind9.16-32:9.16.23-0.14.el8_8.9, bind9.16-dnssec-utils-32:9.16.23-0.14.el8_8.9, bind9.16-libs-32:9.16.23-0.14.el8_8.9
    • Red Hat Enterprise Linux AppStream TUS (v.8.8) bind9.16-32:9.16.23-0.14.el8_8.9, bind9.16-dnssec-utils-32:9.16.23-0.14.el8_8.9, bind9.16-libs-32:9.16.23-0.14.el8_8.9
  • RHSA-2026:70615 Released 2026-10-01 · Red Hat rating Important
    OpenShift Container Platform 4.18.56 bug fix and security update
    • Red Hat OpenShift Container Platform 4.18 rhcos-aarch64-418.94.202609171815-0, rhcos-ppc64le-418.94.202609171815-0, rhcos-s390x-418.94.202609171815-0 +1
  • RHSA-2026:70586 Released 2026-10-01 · Red Hat rating Important
    OpenShift Container Platform 4.17.58 bug fix and security update
    • Red Hat OpenShift Container Platform 4.17 rhcos-aarch64-417.94.202609191027-0, rhcos-ppc64le-417.94.202609191027-0, rhcos-s390x-417.94.202609191027-0 +1
  • RHSA-2026:65851 Released 2026-09-17 · Red Hat rating Important
    OpenShift Container Platform 4.18.55 bug fix and security update
    • Red Hat OpenShift Container Platform 4.18 rhcos-aarch64-418.94.202609031320-0, rhcos-ppc64le-418.94.202609031320-0, rhcos-s390x-418.94.202609031320-0 +1
  • RHSA-2026:62549 Released 2026-09-10 · Red Hat rating Important
    OpenShift Container Platform 4.16.70 bug fix and security update
    • Red Hat OpenShift Container Platform 4.16 rhcos-aarch64-416.94.202609011112-0, rhcos-ppc64le-416.94.202609011112-0, rhcos-s390x-416.94.202609011112-0 +1
  • RHSA-2026:60383 Released 2026-08-26 · Red Hat rating Important
    bind security update
    • Red Hat Enterprise Linux Server (v. 7 ELS) bind-32:9.11.4-26.P2.el7_9.21, bind-export-libs-32:9.11.4-26.P2.el7_9.21, bind-export-libs-32:9.11.4-26.P2.el7_9.21.ppc +6
    • Red Hat Enterprise Linux Server Optional (v. 7 ELS) bind-sdb-32:9.11.4-26.P2.el7_9.21
  • RHSA-2026:57189 Released 2026-08-19 · Red Hat rating Important
    bind security update
    • Red Hat Enterprise Linux AppStream E4S (v.9.4) bind-32:9.16.23-18.el9_4.12, bind-chroot-32:9.16.23-18.el9_4.12, bind-dnssec-doc-32:9.16.23-18.el9_4.12 +5
  • RHSA-2026:55441 Released 2026-08-17 · Red Hat rating Important
    bind security update
    • Red Hat CodeReady Linux Builder EUS (v.9.6) bind-libs-32:9.16.23-31.el9_6.4
    • Red Hat Enterprise Linux AppStream EUS (v.9.6) bind-32:9.16.23-31.el9_6.4, bind-dnssec-utils-32:9.16.23-31.el9_6.4, bind-libs-32:9.16.23-31.el9_6.4 +1
  • RHSA-2026:24368 Released 2026-06-08 · Red Hat rating Important
    bind9.18 security update
    • Red Hat Enterprise Linux AppStream (v. 9) bind9.18-32:9.18.29-14.el9_8.2, bind9.18-chroot-32:9.18.29-14.el9_8.2, bind9.18-dnssec-utils-32:9.18.29-14.el9_8.2 +2
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) bind9.18-devel-32:9.18.29-14.el9_8.2, bind9.18-doc-32:9.18.29-14.el9_8.2, bind9.18-libs-32:9.18.29-14.el9_8.2
  • RHSA-2026:24367 Released 2026-06-08 · Red Hat rating Important
    bind security update
    • Red Hat Enterprise Linux AppStream (v. 9) bind-32:9.16.23-40.el9_8.2, bind-chroot-32:9.16.23-40.el9_8.2, bind-dnssec-doc-32:9.16.23-40.el9_8.2 +5
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) bind-devel-32:9.16.23-40.el9_8.2, bind-doc-32:9.16.23-40.el9_8.2, bind-libs-32:9.16.23-40.el9_8.2
  • RHSA-2026:24339 Released 2026-06-08 · Red Hat rating Important
    bind security update
    • Red Hat Enterprise Linux AppStream (v. 8) bind-32:9.11.36-16.el8_10.8, bind-chroot-32:9.11.36-16.el8_10.8, bind-devel-32:9.11.36-16.el8_10.8 +12
    • Red Hat Enterprise Linux BaseOS (v. 8) bind-32:9.11.36-16.el8_10.8, bind-export-devel-32:9.11.36-16.el8_10.8, bind-export-libs-32:9.11.36-16.el8_10.8
  • RHSA-2026:24338 Released 2026-06-08 · Red Hat rating Important
    bind security update
    • Red Hat Enterprise Linux AppStream (v. 10) bind-32:9.18.33-15.el10_2.2, bind-chroot-32:9.18.33-15.el10_2.2, bind-dnssec-utils-32:9.18.33-15.el10_2.2 +3
    • Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) bind-devel-32:9.18.33-15.el10_2.2, bind-doc-32:9.18.33-15.el10_2.2
  • RHSA-2026:23360 Released 2026-06-04 · Red Hat rating Important
    bind9.16 security update
    • Red Hat Enterprise Linux AppStream (v. 8) bind9.16-32:9.16.23-0.22.el8_10.6, bind9.16-chroot-32:9.16.23-0.22.el8_10.6, bind9.16-dnssec-utils-32:9.16.23-0.22.el8_10.6 +4
    • Red Hat Enterprise Linux CRB (v. 8) bind9.16-devel-32:9.16.23-0.22.el8_10.6, bind9.16-doc-32:9.16.23-0.22.el8_10.6, bind9.16-libs-32:9.16.23-0.22.el8_10.6
  • RHSA-2026:20334 Released 2026-05-21 · Red Hat rating Important
    Red Hat Hardened Images RPMs bug fix and enhancement update
    • Red Hat Hardened Images bind-9.18.49-1.hum1@aarch64, bind-9.18.49-1.hum1@src, bind-9.18.49-1.hum1@x86_64 +12

Vendor assessments

Red Hat

Red Hat rating: Important. Red Hat's page for this CVE →

ProductStatusPlan or fix
Red Hat OpenShift Container Platform 4AffectedNo fix yet
Red Hat CodeReady Linux Builder EUS (v.9.6)Fixed RHSA-2026:55441, RHSA-2026:94278
Red Hat Enterprise Linux AppStream (v. 10)Fixed RHSA-2026:24338
Red Hat Enterprise Linux AppStream (v. 8)Fixed RHSA-2026:23360, RHSA-2026:24339
Red Hat Enterprise Linux AppStream (v. 9)Fixed RHSA-2026:24367, RHSA-2026:24368
Red Hat Enterprise Linux AppStream AUS (v.8.4)Fixed RHSA-2026:95477
Red Hat Enterprise Linux AppStream AUS (v.8.6)Fixed RHSA-2026:94277, RHSA-2026:95435
Red Hat Enterprise Linux AppStream E4S (v.8.8)Fixed RHSA-2026:79160, RHSA-2026:95478
Red Hat Enterprise Linux AppStream E4S (v.9.2)Fixed RHSA-2026:95242
Red Hat Enterprise Linux AppStream E4S (v.9.4)Fixed RHSA-2026:57189
Red Hat Enterprise Linux AppStream EUS (v. 10.0)Fixed RHSA-2026:94115
Red Hat Enterprise Linux AppStream EUS (v.9.6)Fixed RHSA-2026:55441, RHSA-2026:94278
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)Fixed RHSA-2026:95477
Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)Fixed RHSA-2026:94277, RHSA-2026:95435
Red Hat Enterprise Linux AppStream TUS (v.8.8)Fixed RHSA-2026:79160, RHSA-2026:95478
Red Hat Enterprise Linux BaseOS (v. 8)Fixed RHSA-2026:24339
Red Hat Enterprise Linux BaseOS AUS (v.8.4)Fixed RHSA-2026:95477
Red Hat Enterprise Linux BaseOS AUS (v.8.6)Fixed RHSA-2026:95435
Red Hat Enterprise Linux BaseOS E4S (v.8.8)Fixed RHSA-2026:95478
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)Fixed RHSA-2026:95477
Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.6)Fixed RHSA-2026:95435
Red Hat Enterprise Linux BaseOS TUS (v.8.8)Fixed RHSA-2026:95478
Red Hat Enterprise Linux CRB (v. 8)Fixed RHSA-2026:23360
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)Fixed RHSA-2026:24338
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)Fixed RHSA-2026:24367, RHSA-2026:24368
Red Hat Enterprise Linux Server (v. 7 ELS)Fixed RHSA-2026:60383
Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION)Fixed RHSA-2026:95727
Red Hat Enterprise Linux Server Optional (v. 7 ELS)Fixed RHSA-2026:60383
Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION)Fixed RHSA-2026:95727
Red Hat Hardened ImagesFixed RHSA-2026:20334
Red Hat OpenShift Container Platform 4.16Fixed RHSA-2026:62549
Red Hat OpenShift Container Platform 4.17Fixed RHSA-2026:70586
Red Hat OpenShift Container Platform 4.18Fixed RHSA-2026:65851, RHSA-2026:70615
Not affected: 20 products
  • Red Hat CodeReady Linux Builder EUS (v.9.6)
  • Red Hat Enterprise Linux 9
  • Red Hat Enterprise Linux AppStream AUS (v.8.4)
  • Red Hat Enterprise Linux AppStream AUS (v.8.6)
  • Red Hat Enterprise Linux AppStream E4S (v.8.8)
  • Red Hat Enterprise Linux AppStream E4S (v.9.2)
  • Red Hat Enterprise Linux AppStream EUS (v. 10.0)
  • Red Hat Enterprise Linux AppStream EUS (v.9.6)
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4)
  • Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6)
  • Red Hat Enterprise Linux AppStream TUS (v.8.8)
  • Red Hat Enterprise Linux BaseOS AUS (v.8.4)
  • Red Hat Enterprise Linux BaseOS E4S (v.8.8)
  • Red Hat Enterprise Linux BaseOS EUS EXTENSION (v.8.4)
  • Red Hat Enterprise Linux BaseOS TUS (v.8.8)
  • Red Hat Enterprise Linux CodeReady Linux Builder EUS (v. 10.0)
  • Red Hat Enterprise Linux Server (v. 7 ELS)
  • Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION)
  • Red Hat Enterprise Linux Server Optional (v. 7 ELS)
  • Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION)

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-5946
  2. 2026-10-03 Alias added: GHSA-cqgq-ff3f-rj7r
  3. 2026-10-09 Fix available: RHSA-2026:79160 · Red Hat
  4. 2026-10-09 Fix available: Red Hat Enterprise Linux AppStream E4S (v.8.8), Red Hat Enterprise Linux AppStream TUS (v.8.8) · Red Hat
  5. 2026-11-03 Fix available: RHSA-2026:94115 · Red Hat
  6. 2026-11-03 Fix available: RHSA-2026:94277 · Red Hat
  7. 2026-11-03 Fix available: RHSA-2026:94278 · Red Hat
  8. 2026-11-03 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.6), Red Hat Enterprise Linux AppStream EUS (v. 10.0), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.6) · Red Hat
  9. 2026-11-04 Fix available: RHSA-2026:95242 · Red Hat
  10. 2026-11-04 Fix available: Red Hat Enterprise Linux AppStream E4S (v.9.2) · Red Hat
  11. 2026-11-05 Fix available: Red Hat Enterprise Linux AppStream AUS (v.8.4), Red Hat Enterprise Linux AppStream EUS EXTENSION (v.8.4), Red Hat Enterprise Linux BaseOS AUS (v.8.4) +5 · Red Hat
  12. 2026-11-06 Fix available: RHSA-2026:95477 · Red Hat
  13. 2026-11-06 Fix available: RHSA-2026:95435 · Red Hat
  14. 2026-11-06 Fix available: RHSA-2026:95478 · Red Hat
  15. 2026-11-06 Fix available: Red Hat Enterprise Linux Server -EXTENSION(v. 6 ELS-EXTENSION), Red Hat Enterprise Linux Server Optional -EXTENSION (v. 6 ELS -EXTENSION) · Red Hat
  16. 2026-11-06 Fix available: RHSA-2026:95727 · Red Hat

References

Patch 3

Advisory 1

  • TI-2015-04610 Assertion failure in ISC BIND named via TKEY queries KEVCVSS 3.1HIGH 7.5
  • TI-2023-27571 Certain DNSSEC aspects of the DNS protocol (in RFC 4033, 4034, 4035, 6840, and related… CVSS 3.1HIGH 7.5
  • TI-2021-07476 A second vulnerability in BIND's GSSAPI security policy negotiation can be targeted by a buffer overflow attack CVSS 3.1CRITICAL 9.8
  • TI-2023-27773 The Closest Encloser Proof aspect of the DNS protocol (in RFC 5155 when RFC 9276 guidance… CVSS 3.1HIGH 7.5
  • TI-2020-06910 A logic error in code which checks TSIG validity can be used to trigger an assertion failure in tsig.c CVSS 3.1HIGH 7.5
  • TI-2016-02320 buffer.c in named in ISC BIND 9 before 9.9.9-P3, 9.10.x before 9.10.4-P3, and 9.11.x… CVSS 3.0HIGH 7.5
See all 192 →

Sources

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