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TI-2025-27238 Aliases CVE-2025-40776GHSA-2hm8-9847-q7gc

Birthday Attack against Resolvers supporting ECS

Priority MEDIUM 43CWE-349Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
—
Confidentiality · integrity · availability
None · High · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA.

Summary

A `named` caching resolver that is configured to send ECS (EDNS Client Subnet) options may be vulnerable to a cache-poisoning attack. This issue affects BIND 9 versions 9.11.3-S1 through 9.16.50-S1, 9.18.11-S1 through 9.18.37-S1, and 9.20.9-S1 through 9.20.10-S1.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00227 13th percentileScored 2026-11-07
Fix Fixed BIND 9 (ISC): 9.0.0

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 99.11.3-S1 – 9.16.50-S1; 9.18.11-S1 – 9.18.37-S1; 9.20.9-S1 – 9.20.10-S19.0.0Patch availableCNA
  • BIND 9 VendorISC Affected 9.11.3-S1 – 9.16.50-S1; 9.18.11-S1 – 9.18.37-S1; 9.20.9-S1 – 9.20.10-S1 Fixed in 9.0.0 Patch available CNA

CPE names Threatist (inferred) · 1

Inferred from how NVD named this product before; not given by a source.

CPEVersionsRoleVendor
cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:*——ISC
  • cpe:2.3:a:isc:bind:*:*:*:*:*:*:*:* Versions — — ·ISC

Remediation

  • Fix · CNA BIND 9 (ISC) Fixed in 9.0.0

Vendor assessments

Red Hat

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

Not affected: 8 products
  • Red Hat Enterprise Linux 10
  • Red Hat Enterprise Linux 6
  • Red Hat Enterprise Linux 7
  • Red Hat Enterprise Linux 8
  • Red Hat Enterprise Linux 9
  • Red Hat Hardened Images
  • Red Hat OpenShift Container Platform 4
  • Red Hat OpenShift Container Platform 5

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-40776
  2. 2026-10-03 Alias added: GHSA-2hm8-9847-q7gc
  3. 2026-11-05 Affected versions changed · Red Hat

References

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-1999-00042 Command execution via shell metachars in INN daemon (innd) 1.5 using "newgroup" and… 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-2025-27240 Cache poisoning attacks with unsolicited RRs CVSS 3.1HIGH 8.6
See all 285 →

Sources

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