NSEC3 insecure-referral proof can use unrelated cached NSEC3 RRsets
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- High
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · High · None
- Fix status
- Partial Red Hat: 1 fixed, 6 without a fix
Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-346.
Summary
A validly signed NSEC3 from an unrelated sibling zone may be accepted as an insecurity proof, downgrading a secure delegation and letting a forged unsigned answer through. 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.
Why it matters now
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| ISC | BIND 9 | 9.11.0 – 9.18.50; 9.20.0 – 9.20.27; 9.21.0 – 9.21.25; 9.11.3-S1 – 9.18.50-S1; 9.20.9-S1 – 9.20.27-S1 | — | No fix listed | CNA |
- BIND 9 VendorISC Affected 9.11.0 – 9.18.50; 9.20.0 – 9.20.27; 9.21.0 – 9.21.25; 9.11.3-S1 – 9.18.50-S1; 9.20.9-S1 – 9.20.27-S1 Fixed in — No fix listed CNA
Remediation
Red Hat 1 advisory
- RHSA-2026:68279 Released 2026-09-16 · Red Hat rating ImportantRed Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images bind-32:9.20.29-0.1.hum1@aarch64, bind-32:9.20.29-0.1.hum1@src, bind-32:9.20.29-0.1.hum1@x86_64 +12
Vendor assessments
Red Hat
Red Hat rating: Moderate. Red Hat's page for this CVE →
| Product | Status | Plan or fix |
|---|---|---|
| Red Hat Enterprise Linux 10 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 7 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 8 | Affected | No fix yet: Fix deferred |
| Red Hat Enterprise Linux 9 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 4 | Affected | No fix yet: Fix deferred |
| Red Hat OpenShift Container Platform 5 | Affected | No fix yet: Fix deferred |
| Red Hat Hardened Images | Fixed | RHSA-2026:68279 |
Not affected: 2 products
- Red Hat Enterprise Linux 6
- Red Hat Enterprise Linux 9
Timeline
- 2026-10-02 Threatist record created from CVE-2026-77119
- 2026-10-03 Alias added: GHSA-r3pf-h3x3-rv3w
- 2026-11-06 Affected versions changed · Red Hat
References
More ISC vulnerabilities
- 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
Sources
- CVE-2026-77119 · CVE Program
- CVE-2026-77119 · NVD
- FIRST EPSS
- GHSA-r3pf-h3x3-rv3w · GitHub Advisory Database · CC BY 4.0
- CVE-2026-77119 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences