Answer in brief
CVE-2026-123578 records a Medium severity (CVSS 6.3) vulnerability in Hickory DNS 0.26.0 before 0.26.2 Response Validation Bypass via QDCOUNT=0. The current sources do not mark it as known exploited. The current feed maps hickory-dns/hickory-dns (generic), hickory-dns/hickory-dns (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 6.3. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps hickory-dns/hickory-dns (generic), hickory-dns/hickory-dns (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| hickory-dns/hickory-dnsgeneric | >=0.26.0 <0.26.2 | 0.26.2 |
| hickory-dns/hickory-dnsgeneric | >=0.25.0 <=0.25.2 | Not reported |
Published upstream
Nov 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Nov 8, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Nov 8, 2026
Hickory DNS hickory-net 0.26.0 before 0.26.2 and hickory-proto 0.25.0 through 0.25.2 skip the check that a UDP response's question section matches the query when the response has an empty question section (QDCOUNT=0), and also skip the case-randomization check. Remote attackers able to inject spoofed UDP responses can send QDCOUNT=0 responses to bypass these checks, weakening defenses against DNS spoofing.
Quoted source text, attributed separately from HOL analysis.