TI-2026-32581 Aliases CVE-2026-44690 GHSA-jwg4-375h-655h

Cross-zone wildcard cache poisoning via RRSIG.labels manipulation

LOW 38CWE-345Published 2026-07-22 · Updated 2026-07-22

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: Security bypass
Confidentiality · integrity · availability: None · High · None
Fix status: Partial Red Hat: 7 fixed, 2 without a fix

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and Red Hat. Impact type from CWE-345.

Summary

In NLnet Labs Unbound 1.7.0 up to and including 1.25.1, insufficient validation of the RRSIG.Labels field combined with premature cache writes during RFC 8198 aggressive NSEC processing leads to cache poisoning that permits a malicious actor controlling a single delegated zone to poison arbitrary sibling zones under NSEC-signed parent domains. A malicious actor with one registered domain under an NSEC-signed TLD can serve malicious insecure DNS responses for unrelated sibling domains (sharing the same parent zone). Arbitrary delegations that do not exist under the parent domain and are covered by the parent's NSEC chain can be brought into insecure existence by fraudulent wildcard DS records (less labels than expected, unknown algorithm) from the malicious sibling domain. This allows the malicious actor to inject insecure wildcard records for those delegations.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV

EPSS 0.00153 4th percentileScored 2026-11-07

Fix Partial Unbound (NLnet Labs): 1.25.2Red Hat: 5 advisoriesRed Hat: 7 fixed, 2 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

Vendor	Product	Affected versions	Fixed in	Status	Source
NLnet Labs	Unbound	1.7.0 to before 1.25.2	1.25.2	Patch available	CNA

Unbound VendorNLnet Labs Affected 1.7.0 to before 1.25.2 Fixed in 1.25.2 Patch available CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:nlnetlabs:unbound::::::::	1.7.0 to before 1.25.2	Vulnerable	NLNETLABS

cpe:2.3:a:nlnetlabs:unbound:*:*:*:*:*:*:*:* Versions 1.7.0 to before 1.25.2 Vulnerable ·NLNETLABS

Remediation

Fix · CNA Unbound (NLnet Labs) Fixed in 1.25.2

Red Hat 5 advisories

RHSA-2026:60440 Released 2026-09-01 · Red Hat rating Important
OpenShift Container Platform 4.22.12 bug fix and security update
- Red Hat OpenShift Container Platform 4.22 rhcos-aarch64-4.22.9.8.202608251819-0, rhcos-ppc64le-4.22.9.8.202608251819-0, rhcos-s390x-4.22.9.8.202608251819-0 +1
RHSA-2026:55892 Released 2026-08-17 · Red Hat rating Important
unbound security update
- Red Hat Enterprise Linux AppStream (v. 10) python3-unbound-1.24.2-7.el10_2.4, unbound-1.24.2-7.el10_2.4, unbound-anchor-1.24.2-7.el10_2.4 +3
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 10) unbound-devel-1.24.2-7.el10_2.4
RHSA-2026:55841 Released 2026-08-17 · Red Hat rating Important
unbound security update
- Red Hat Enterprise Linux AppStream (v. 9) python3-unbound-1.24.2-3.el9_8.4, unbound-1.24.2-3.el9_8.4, unbound-dracut-1.24.2-3.el9_8.4 +1
- Red Hat Enterprise Linux CodeReady Linux Builder (v. 9) unbound-devel-1.24.2-3.el9_8.4

Show 2 more Red Hat advisories

RHSA-2026:55784 Released 2026-08-17 · Red Hat rating Important
unbound security update
- Red Hat Enterprise Linux AppStream (v. 8) python3-unbound-1.16.2-5.14.el8_10, unbound-1.16.2-5.14.el8_10, unbound-devel-1.16.2-5.14.el8_10 +1
RHSA-2026:43588 Released 2026-07-22 · Red Hat rating Important
Red Hat Hardened Images RPMs bug fix and enhancement update
- Red Hat Hardened Images python3-unbound-1.25.2-0.1.hum1@aarch64, python3-unbound-1.25.2-0.1.hum1@x86_64, unbound-1.25.2-0.1.hum1@aarch64 +14

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Release · 2026-07-22
NLnet Labs Unbound 1.25.2
24 records Highest priority Priority LOW 24 LOW
Other records, highest priority first
- TI-2026-40374 'dns-error-reporting: yes' leads to stack buffer overflowPriority LOW 39
- TI-2026-29375 Packet of death for DNSCrypt over TCPPriority LOW 39
- TI-2026-25166 Remote DNS-over-QUIC denial of service due to `quic-size` budget bypassPriority LOW 39
Show all 24 records →

Vendor assessments

Red Hat

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

Product	Status	Plan or fix
Red Hat OpenShift Container Platform 4	Affected	No fix yet
Red Hat OpenShift Container Platform 5	Affected	No fix yet
Red Hat Enterprise Linux AppStream (v. 10)	Fixed	RHSA-2026:55892
Red Hat Enterprise Linux AppStream (v. 8)	Fixed	RHSA-2026:55784
Red Hat Enterprise Linux AppStream (v. 9)	Fixed	RHSA-2026:55841
Red Hat Enterprise Linux CodeReady Linux Builder (v. 10)	Fixed	RHSA-2026:55892
Red Hat Enterprise Linux CodeReady Linux Builder (v. 9)	Fixed	RHSA-2026:55841
Red Hat Hardened Images	Fixed	RHSA-2026:43588
Red Hat OpenShift Container Platform 4.22	Fixed	RHSA-2026:60440

Not affected: 2 products

Red Hat Enterprise Linux 6
Red Hat Enterprise Linux 7

Timeline

2026-10-02 Threatist record created from CVE-2026-44690
2026-10-03 Alias added: GHSA-jwg4-375h-655h
2026-11-02 Affected versions changed · Red Hat

References

Advisory 1

https://www.nlnetlabs.nl/downloads/unbound/CVE-2026-44690.txt

TI-2026-25690 Possible arbitrary code execution during DNSSEC validation CVSS 4.0CRITICAL 9.1
TI-2026-56302 Heap buffer overflow and possible Remote Code Execution when digesting DNSKEY CVSS 4.0CRITICAL 9.1
TI-2026-31146 Crash during DNSSEC validation of malicious content CVSS 4.0HIGH 8.7
TI-2026-31135 Heap overflow with multiple NSID, COOKIE, PADDING EDNS options CVSS 4.0HIGH 8.7
TI-2026-36436 Routinator crashes on specifically crafted RRDP XML files CVSS 4.0HIGH 8.7
TI-2026-36433 Routinator exits when accepting an incoming HTTP or RTR connection fails CVSS 4.0HIGH 8.7

See all 96 →

Sources

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