In NLnet Labs Unbound 1.22.0 up to and including 1.25.1, when downstream DNS-over-QUIC (DoQ) is enabled, the first two bidirectional streams on a new QUIC connection (stream_id 0 and 4) bypass the per-stream 'quic-size' gate entirely, and large input buffers are allocated later, after only the 2-byte length prefix has been received from the initial streams. As a result, a remote client can make Unbound exceed the configured 'quic-size' limit with low-cost input. Using only one connection and two streams, each sending a declared 65535-byte length prefix and then holding the streams open, a client can already trivially make Unbound roughly allocate double that amount. This is a remote availability issue / memory-accounting bypass in the downstream DoQ implementation that leads to denial of service for new DoQ clients. This vulnerability needs Unbound to be compiled with DoQ support ('--with-libngtcp2') and the 'quic-port' to be configured for the listening interfaces.
CVE-2026-32665
Score 7.5 from GitHub Security Advisory (severity: HIGH) published 2026-07-22. a secondary CVSS source baseline 7.5; sources differ by 0.0.
- High severity, but no confirmed exploitation yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 7.5
- EG Score
- 7.5(high)
- EG Risk
- 49(Track)EG Risk 49/100SSVC: Track
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity75% × 45%Exploitation0% × 40%Automatability100% × 15%Action: Routine — remediate on your standard cadence. - EPSS
- —
- KEV
- Not listed
Published
July 22, 2026
Last Modified
July 22, 2026
Advisory Details (1)
Auto-updated Jul 22, 2026Vendor Advisories for CVE-2026-32665(1)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 7× in last 7d / 7× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-23 03:09 UTCEG score recompute
- 2026-07-22 22:04 UTCEG score recompute
- 2026-07-22 22:04 UTCGHSA enrichment
- 2026-07-22 15:34 UTCEG score recompute
- 2026-07-22 15:34 UTCGHSA enrichment
- 2026-07-22 13:19 UTCEG score recompute
- 2026-07-22 13:17 UTCMITRE cvelistV5first tracked
Frequently asked(4)
What is CVE-2026-32665?
When was CVE-2026-32665 disclosed?
What is the CVSS score of CVE-2026-32665?
How do I remediate CVE-2026-32665?
Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-32665
Is Your Infrastructure Affected by CVE-2026-32665?
EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.