CVE-2025-8671

Description

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.

Scores

EPSS (exploitation in 30 days)

3.6% · top 10% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: poc · Automatable: yes · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: High 7.5.

Weakness

• CWE-404 Improper Resource Shutdown or Release
• CWE-404 Improper Resource Shutdown or Release (opens in a new tab)All about CWE-404 and its CVEs

Affected products

• SUSE Linux · Enterprise Module for Development Tools

  • affected 15 SP2 – < 15-SP5

• SUSE Linux · Enterprise High Performance Computing (HPC)

  • affected 15 – < 15 SP5

• Varnish Software · Varnish Enterprise

  • affected 6.0.x – ≤ 6.0.14r4

• Varnish Software · Varnish Cache

  • affected 6.0LTS – ≤ 6.014

• Varnish Software · Varnish Cache

  • affected 5.x – ≤ 7.71

• Fastly · H20

  • affected 579ecfa

• Wind River · Linux

  • affected LTS22 – ≤ TLS25

• SUSE Linux · Enterprise Desktop

  • affected 15 SP6 – < 15 SP7

• SUSE Linux · Enterprise High Performance Computing

  • affected 15 SP3 – < 15 SP7

• SUSE Linux · Enterprise Module for Dev Tools

  • affected 15 SP3 – < 15 SP7

• SUSE Linux · Enterprise Module for Package Hub

  • affected 15 SP5 – < 15 SP7

• SUSE Linux · Enterprise Server

  • affected 12 SP5 – < 15 SP7

• SUSE Linux · Enterprise Server for SAP Applications

  • affected 15 SP6 – < 15 SP7

• SUSE Linux · SUSE Manager Server

  • affected 4.3

• SUSE Linux · SUSE Manager Server LTS

  • affected 4.3

• SUSE Linux · SUSE Manager Proxy

  • affected 4.3

• SUSE Linux · SUSE Manager Retail Branch Server

  • affected 4.3

• SUSE Linux · openSUSE Leap

  • affected 15.6

References (17)

• https://galbarnahum.com/made-you-reset (opens in a new tab)
• https://kb.cert.org/vuls/id/767506 (opens in a new tab)
• https://varnish-cache.org/security/VSV00017.html (opens in a new tab)
• https://www.fastlystatus.com/incident/377810 (opens in a new tab)
• https://github.com/h2o/h2o/commit/4729b661e3c6654198d2cc62997e1af58bef4b80 (opens in a new tab)
• https://support2.windriver.com/index.php?page=security-notices (opens in a new tab)
• https://www.suse.com/support/kb/doc/?id=000021980 (opens in a new tab)
• https://gitlab.isc.org/isc-projects/bind9/-/issues/5325 (opens in a new tab)exploit
• https://github.com/h2o/h2o/security/advisories/GHSA-mrjm-qq9m-9mjq (opens in a new tab)
• https://github.com/envoyproxy/envoy/issues/40739 (opens in a new tab)
• https://github.com/varnish/hitch/issues/397 (opens in a new tab)
• https://github.com/Kong/kong/discussions/14731 (opens in a new tab)
• https://deepness-lab.org/publications/madeyoureset/ (opens in a new tab)
• https://www.imperva.com/blog/madeyoureset-turning-http-2-server-against-itself/ (opens in a new tab)
• https://www.kb.cert.org/vuls/id/767506 (opens in a new tab)
• http://www.openwall.com/lists/oss-security/2025/09/18/1 (opens in a new tab)
• http://www.openwall.com/lists/oss-security/2025/08/13/6 (opens in a new tab)

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2025-8671](https://trackcve.app/badge/CVE-2025-8671.svg)](https://trackcve.app/cve/CVE-2025-8671)

Record last updated 4 Nov 2025, 21:15 UTC.