Parsing an invalid SVCB or HTTPS RR can panic in golang.org/x/net/dns/dnsmessage (CVE-2026-46600) | HOL Guard CVE

High · CVSS 7.5CVE-2026-46600

Parsing an invalid SVCB or HTTPS RR can panic in golang.org/x/net/dns/dnsmessage

Answer in brief

CVE-2026-46600 records a High severity (CVSS 7.5) vulnerability in Parsing an invalid SVCB or HTTPS RR can panic in golang.org/x/net/dns/dnsmessage. The current sources do not mark it as known exploited. The current feed maps golang.org/x/net/golang.org/x/net/dns/dnsmessage (generic), Go standard library/net (generic), Go standard library/net (generic), golang.org/x/net (go) and additional mapped packages. Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Jul 21, 2026Updated Aug 17, 2026Source checked Sep 28, 2026First seen by HOL Aug 13, 2026Material review Aug 17, 2026

Upstream Advisory

Key facts

Risk: High · CVSS 7.5
Exploitation: Not marked as known exploited
Affected software: 6 mapped packages or products
Fix availability: Available

Why this deserves its current priority

CVSS is 7.5. 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.

Affected scope and exposure questions

The current feed maps golang.org/x/net/golang.org/x/net/dns/dnsmessage (generic), Go standard library/net (generic), Go standard library/net (generic), golang.org/x/net (go) and additional mapped packages. Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
golang.org/x/net/golang.org/x/net/dns/dnsmessagegeneric	>=0 <0.56.0	0.56.0
Go standard library/netgeneric	>=0 <1.26.6 \|\| >=1.27.0-0 <1.27.0-rc.3	1.26.6, 1.27.0-rc.3
Go standard library/netgeneric	>=1.26.0-0 <1.26.6 \|\| >=1.27.0-0 <1.27.0-rc.3	1.26.6, 1.27.0-rc.3
golang.org/x/netgo	>=0 <0.56.0	0.56.0
stdlibgo	>=0 <1.26.6 >=1.27.0-0 <1.27.0-rc.3	1.26.6, 1.27.0-rc.3
stdlibgo	>=1.26.0-0 <1.26.6 >=1.27.0-0 <1.27.0-rc.3	1.26.6, 1.27.0-rc.3

Recommended response

Check inventory. Check lockfiles and deployed manifests for golang.org/x/net/golang.org/x/net/dns/dnsmessage, Go standard library/net, Go standard library/net.
Review the reported fix. Update golang.org/x/net/golang.org/x/net/dns/dnsmessage to 0.56.0; Go standard library/net to 1.26.6; Go standard library/net to 1.26.6; golang.org/x/net to 0.56.0; stdlib to 1.26.6; stdlib to 1.26.6 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Jul 21, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Aug 17, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Aug 13, 2026

Sources and claim methodology

Upstream source description

Parsing an invalid SVCB or HTTPS RR can panic when the size of a parameter value overflows the message buffer.

Quoted source text, attributed separately from HOL analysis.