CVE-2026-78660

Historically, we have been rather lax about malformed framing-related headers in our HTTP/2 implementation, as they cannot interfere with HTTP/2 framing. However, this makes it possible for our HTTP/2 implementation to forward responses containing such headers to an HTTP/1 client when acting as a reverse proxy. If the HTTP/1 client also does not behave strictly enough, this can result in response smuggling.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://go.dev/cl/835145
https://go.dev/cl/836385
https://go.dev/issue/81115
https://groups.google.com/g/golang-announce/c/U2fTuyDJznI
https://pkg.go.dev/vuln/GO-2026-6610

Configurations

No configuration.

History

09 Oct 2026, 17:16

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 7.5
CWE		CWE-444

08 Oct 2026, 23:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 23:17

Updated : 2026-10-09 17:16

NVD link : CVE-2026-78660

Mitre link : CVE-2026-78660

CVE.ORG link : CVE-2026-78660

JSON object : View

Products Affected

No product.

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

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