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 3.1
- 7.5
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N - EPSS
- 0.4% chance of exploitation in the next 30 days; higher than 36% of CVEs (scores of 2026-10-25)
- CWE
- CWE-444
- Published
- Modified
- Record from
- the NVD, synced
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GO-2026-6610 | Go | stdlib | <1.26.9 | 1.26.9 |
| GO-2026-6610 | Go | stdlib | >=1.27.0-0 <1.27.2 | 1.27.2 |
| GO-2026-6610 | Go | golang.org/x/net | <0.60.0 | 0.60.0 |