CVE-2026-78663
Published: October 9, 2026Last modified: October 12, 2026
Description
The HTTP/2 server can refund connection-level flow control twice for the same data: Once when a client resets a stream (refunding data for any sent-but-unread portion of the stream), and again when a request handler reads the buffered data. A malicious client can exploit this to bypass the configured connection-level flow control limit (MaxReceiveBufferPerConnection). Total buffered data is still limited by the concurrent stream limit and stream-level flow control.
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 9.1 |
| Attack Vector | NETWORK |
| Attack complexity | LOW |
| Privileges required | NONE |
| User interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality | NONE |
| Integrity impact | HIGH |
| Availability impact | HIGH |
| Vector | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H |
Status
| Product | Release | Package | Status |
|---|---|---|---|
| Alpaquita Linux | 23 LTS | buildah | Unknown (1.28.0-r1) |
| containerd | Unknown (1.6.10-r0) | ||
| go | Unknown (1.19.7-r0) | ||
| podman | Unknown (4.3.1-r0) | ||
| runc | Unknown (1.1.4-r3) | ||
| skopeo | Unknown (1.10.0-r2) | ||
| 25 LTS | buildah | Unknown (1.40.0-r0) | |
| calicoctl | Unknown (3.31.3-r0) | ||
| cilium-cli | Unknown (0.19.0-r12) | ||
| cni-plugins | Unknown (1.9.0-r2) | ||
| containerd | Unknown (2.1.1-r0) | ||
| cri-tools | Unknown (1.35.0-r2) | ||
| docker-cli-buildx | Unknown (0.24.0-r0) | ||
| etcd | Unknown (3.6.4-r6) | ||
| go | Unknown (1.24.3-r0) | ||
| google-guest-agent | Unknown (20250521.00-r0) | ||
| helm | Unknown (3.19.0-r4) | ||
| osv-scanner | Unknown (2.1.0-r4) | ||
| podman | Unknown (5.5.0-r0) | ||
| rootlesskit | Unknown (2.3.5-r0) | ||
| runc | Unknown (1.3.0-r1) | ||
| skopeo | Unknown (1.18.0-r2) | ||
| Stream | buildah | Unknown (1.31.0-r0) | |
| calicoctl | Unknown (3.31.3-r0) | ||
| cilium-cli | Unknown (0.19.0-r12) | ||
| cni-plugins | Unknown (1.9.0-r2) | ||
| containerd | Unknown (1.7.2-r1) | ||
| cri-tools | Unknown (1.35.0-r2) | ||
| docker | Fixed (29.9.0-r0) | ||
| docker-cli-buildx | Unknown (0.11.0-r0) | ||
| etcd | Unknown (3.6.4-r6) | ||
| go | Unknown (1.20.5-r2) | ||
| google-guest-agent | Unknown (20250214.01-r0) | ||
| grype | Unknown (0.100.0-r0) | ||
| helm | Unknown (3.19.0-r4) | ||
| osv-scanner | Unknown (2.1.0-r2) | ||
| podman | Unknown (4.5.1-r1) | ||
| rootlesskit | Unknown (2.1.0-r0) | ||
| runc | Unknown (1.1.7-r1) | ||
| skopeo | Unknown (1.13.0-r1) | ||
| Hardened Containers | 23 LTS | go | Unknown (1.19.7-r0) |
| 25 LTS | go | Unknown (1.24.3-r0) | |
| Stream | go | Unknown (1.20.5-r2) |