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TI-2019-12576 Aliases CVE-2019-16866GHSA-gg25-v243-f7cq

Unbound before 1.9.4 accesses uninitialized memory, which allows remote attackers to…

Priority MEDIUM 45CWE-755Published · 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
Deferred Red Hat: fix deferred

Attack profile from CVSS 3.1 · NVD. Fix status from CNA and Red Hat. Impact type from CWE-908 and the CVSS impact.

Summary

Unbound before 1.9.4 accesses uninitialized memory, which allows remote attackers to trigger a crash via a crafted NOTIFY query. The source IP address of the query must match an access-control rule.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.03506 89th percentileScored 2026-11-07
Fix Deferred Red Hat: fix deferred

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
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:*before 1.9.4VulnerableNLNETLABS
cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:*19.04VulnerableCanonical
  • cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:* Versions before 1.9.4 Vulnerable ·NLNETLABS
  • cpe:2.3:o:canonical:ubuntu_linux:19.04:*:*:*:*:*:*:* Versions 19.04 Vulnerable ·Canonical

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

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

ProductStatusPlan or fix
Red Hat Enterprise Linux 8AffectedNo fix yet: Fix deferred
Not affected: 2 products
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7

Timeline

  1. 2026-10-02 Threatist record created from CVE-2019-16866
  2. 2026-10-03 Alias added: GHSA-gg25-v243-f7cq
  3. 2026-10-08 CISA SSVC decision points changed
  4. 2026-10-09 Priority changed: LOW → MEDIUM

References

Patch 1

Advisory 4

Other 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences