CVE catalog

CVE-2025-8671

DNSdist vulnerabilities

Severity: High · CVSS 7.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Published: Aug 13, 2025, 12:03:37 PM UTC
Source: [NVD] · [CVE record]
EPSS: 3.62% · Oct 25, 2026

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.

Vulnerable and fixed packages

Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.

Distribution	Package	Release	Version	Status
Debian	h2o	bookworm	`2.2.5+dfsg2-7`	vulnerable
Debian	haproxy	sid	`3.2.26-1`	not affected
Debian	haproxy	forky	`3.2.26-1`	not affected
Debian	haproxy	trixie	`3.0.11-1+deb13u3`	not affected
Debian	haproxy	trixie-security	`3.0.11-1+deb13u4`	not affected
Debian	haproxy	bookworm	`2.6.12-1+deb12u3`	not affected
Debian	haproxy	bookworm-security	`2.6.12-1+deb12u4`	not affected
Debian	varnish	trixie	`7.7.0-3+deb13u1`	fixed
Debian	varnish	trixie-security	`7.7.0-3+deb13u2`	fixed
Debian	varnish	bookworm	`7.1.1-2+deb12u1`	vulnerable
Debian	varnish	bookworm-security	`7.1.1-2+deb12u1`	vulnerable
Ubuntu	h2o	noble	Not reported	vulnerable
Ubuntu	varnish	noble	Not reported	vulnerable
Ubuntu	dnsdist	noble	`1.8.3-2ubuntu0.1~esm1`	fixed
Alpine	lighttpd	3.15	`0-r0`	fixed
Alpine	lighttpd	3.16	`0-r0`	fixed
Alpine	lighttpd	3.17	`0-r0`	fixed
Alpine	lighttpd	3.18	`0-r0`	fixed
Alpine	lighttpd	3.19	`0-r0`	fixed
Alpine	lighttpd	3.20	`0-r0`	fixed
Alpine	lighttpd	3.21	`0-r0`	fixed
Alpine	lighttpd	3.22	`0-r0`	fixed
Alpine	lighttpd	3.23	`0-r0`	fixed
Alpine	lighttpd	3.24	`0-r0`	fixed
Alpine	varnish	3.22	`7.7.2-r0`	fixed
Alpine	varnish	3.23	`7.7.2-r0`	fixed
Alpine	varnish	3.24	`7.7.2-r0`	fixed
Opensuse	dnsdist	tumbleweed	`2.0.2-1.1`	fixed
Opensuse	lighttpd	tumbleweed	`1.4.80-1.1`	fixed

Fixed-version evidence

Distribution	Package	Type	Release	Fixed version	Urgency	Origin	Bugs
Debian	h2o	source	bookworm	`(unfixed)`	not yet assigned	Not reported	Not reported
Debian	haproxy	source	sid	`Not affected`	unimportant	Not reported	Not reported
Debian	haproxy	source	forky	`Not affected`	unimportant	Not reported	Not reported
Debian	haproxy	source	trixie	`Not affected`	unimportant	Not reported	Not reported
Debian	haproxy	source	bookworm	`Not affected`	unimportant	Not reported	Not reported
Debian	varnish	source	trixie	`7.7.0-3+deb13u1`	not yet assigned	Not reported	Not reported
Debian	varnish	source	bookworm	`(unfixed)`	not yet assigned	Not reported	Not reported
Ubuntu	dnsdist	deb	noble	`1.8.3-2ubuntu0.1~esm1`	Not reported	Not reported	Not reported
Alpine	lighttpd	apk	3.15	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.16	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.17	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.18	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.19	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.20	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.21	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.22	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.23	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	lighttpd	apk	3.24	`0-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	varnish	apk	3.22	`7.7.2-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	varnish	apk	3.23	`7.7.2-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Alpine	varnish	apk	3.24	`7.7.2-r0`	Not reported	ALPINE-CVE-2025-8671	Not reported
Opensuse	dnsdist	rpm	tumbleweed	`2.0.2-1.1`	Not reported	OPENSUSE-SU-2026:10219-1	Not reported
Opensuse	lighttpd	rpm	tumbleweed	`1.4.80-1.1`	Not reported	OPENSUSE-SU-2025:15448-1	Not reported

Notes

[bookworm] h2o: Minor issue [bookworm] varnish: Minor issue, too intrusive to backport

OpenFactory catalog packages

[Debian 12 (Bookworm)]

[h2o]Affected
Details (2)
- 2.2.5+dfsg2-7 · amd64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · arm64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[h2o-doc]Affected
Source package: [h2o]
Details (2)
- 2.2.5+dfsg2-7 · all · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · all · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[libh2o0.13]Affected
Source package: [h2o]
Details (2)
- 2.2.5+dfsg2-7 · amd64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · arm64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[libh2o-dev]Affected
Source package: [h2o]
Details (2)
- 2.2.5+dfsg2-7 · amd64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · arm64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[libh2o-dev-common]Affected
Source package: [h2o]
Details (2)
- 2.2.5+dfsg2-7 · all · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · all · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[libh2o-evloop0.13]Affected
Source package: [h2o]
Details (2)
- 2.2.5+dfsg2-7 · amd64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · arm64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[libh2o-evloop-dev]Affected
Source package: [h2o]
Details (2)
- 2.2.5+dfsg2-7 · amd64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
- 2.2.5+dfsg2-7 · arm64 · bookworm
  Affected
  usn · h2o · debian · bookworm; usn · h2o · debian · 12
[libvarnishapi3]Affected
Source package: [varnish]
Details (4)
- 7.1.1-2+deb12u1 · amd64 · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · arm64 · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · amd64 · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · arm64 · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
[libvarnishapi-dev]Affected
Source package: [varnish]
Details (4)
- 7.1.1-2+deb12u1 · amd64 · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · arm64 · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · amd64 · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · arm64 · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
[varnish]Affected
Details (4)
- 7.1.1-2+deb12u1 · amd64 · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · arm64 · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · amd64 · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · arm64 · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
[varnish-doc]Affected
Source package: [varnish]
Details (4)
- 7.1.1-2+deb12u1 · all · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · all · bookworm
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · all · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12
- 7.1.1-2+deb12u1 · all · bookworm-security
  Affected
  usn · varnish · debian · bookworm; usn · varnish · debian · 12

[openSUSE Tumbleweed]

[lighttpd-mod_authn_dbi]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_authn_gssapi]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_authn_ldap]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_authn_pam]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_authn_sasl]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_deflate]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_gnutls]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_magnet]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed
[lighttpd-mod_maxminddb]Unknown
Source package: [lighttpd]
Details (1)
- 1.4.85-1.2 · x86_64 · tumbleweed
  Unknown · Fixed: 1.4.80-1.1
  Version impact unknown
  usn · lighttpd · opensuse · tumbleweed

Next results

Observed: Oct 27, 2026, 12:31:16 PM UTC

References

[CERT-Bund public advisories] · [Debian Security Tracker] · [FIRST EPSS] · [OSV Package Vulnerability Database] · [Red Hat security advisories and VEX] · [SUSE security advisories and VEX] · [Ubuntu Security Notices (USN)]