CVE-2025-8671

EUVD-2025-24560
A mismatch caused by client-triggered server-sent stream resets between HTTP/2 specifications and the internal architectures of some HTTP/2 implementations may result in excessive server resource consumption leading to denial-of-service (DoS).  By opening streams and then rapidly triggering the server to reset them—using malformed frames or flow control errors—an attacker can exploit incorrect stream accounting. Streams reset by the server are considered closed at the protocol level, even though backend processing continues. This allows a client to cause the server to handle an unbounded number of concurrent streams on a single connection. This CVE will be updated as affected product details are released.
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
7.5 HIGH
NETWORK
LOW
NONE
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 88.27%
Debian logo
Debian Releases
Debian Product
Codename
h2o
bookworm
no-dsa
bullseye
postponed
haproxy
bookworm
2.6.12-1+deb12u3
fixed
bookworm (security)
2.6.12-1+deb12u3
fixed
bullseye
2.2.9-2+deb11u6
fixed
bullseye (security)
2.2.9-2+deb11u7
fixed
forky
3.2.22-1
fixed
sid
3.2.22-1
fixed
trixie
3.0.11-1+deb13u3
fixed
trixie (security)
3.0.11-1+deb13u3
fixed
varnish
bookworm
ignored
bookworm (security)
vulnerable
bullseye
ignored
bullseye (security)
vulnerable
trixie
7.7.0-3+deb13u1
fixed
trixie (security)
7.7.0-3+deb13u1
fixed
Ubuntu logo
Ubuntu Releases
Ubuntu Product
Codename
lighttpd
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
plucky
ignored
questing
ignored
resolute
needs-triage
trusty
needs-triage
xenial
ignored
varnish
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
plucky
ignored
questing
ignored
resolute
not-affected
trusty
needs-triage
xenial
ignored
dnsdist
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
Fixed 1.8.3-2ubuntu0.1~esm1
released
questing
Fixed 1.9.10-1ubuntu0.1
released
resolute
not-affected
xenial
not-affected
h2o
bionic
needs-triage
focal
needs-triage
jammy
needs-triage
noble
needs-triage
plucky
ignored
questing
dne
resolute
dne
haproxy
bionic
not-affected
focal
not-affected
jammy
not-affected
noble
not-affected
plucky
not-affected
questing
not-affected
resolute
not-affected
xenial
not-affected