CVE-2025-8671

HIGHPre-NVD 7.57.5
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

This high-severity CVE scores 7.5 under CISA-ADP (Vulnrichment) CVSS v3.1 (NVD's own analysis pending). EPSS exploit probability: 3.6% (89th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from CISA-ADP (Vulnrichment) CVSS v3.1
Sources: CISA-ADP (Vulnrichment) CVSS v3.1, EPSS
Elevated

Also known asEUVD-2025-24560 (ENISA EUVD)Source: ENISA EUVD

7.5EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • Public exploit or proof-of-concept code is available
CISA-KEV: Not listedEPSS PROB: 3.6%CVSS: 7.5Exploit: Public PoCExposed services: Not assessed

A fix is available — apply it.

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.

CVSS v3
7.5
EG Score
7.5HIGHmedium confidence
EG Risk
65
EG Risk 65/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity75% × 45%
Impact severity (EG Severity): CVSS 7.5 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.
EPSS PROB
3.6%
EPSS %ILE
89th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (7.5): severity, escalated by confirmed exploitation. This CVE's 7.5 is its impact severity (EG Severity), not escalated.

EG Severity
7.5 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.CISA-ADP (Vulnrichment) CVSS v3.1 · CVSS v3.1
EG Likelihood
3.6% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-30). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Attend at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Attend at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; 60 days if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

August 13, 2025

Last Modified

June 17, 2026

Advisory Details (9)

Auto-updated Oct 17, 2026
Patch available. Sources: github, cert, github_commit.
Web page

oss-security - HTTP/2 implementations are vulnerable to "MadeYouReset" DoS attack through HTTP/2 control frames

http://www.openwall.com/lists/oss-security/2025/08/13/6
Web page

https://www.varnish.org/docs/security/vsv00017/

https://varnish-cache.org/security/VSV00017.html
Web page

Safety and Security Notices - Wind River Support Network

https://support2.windriver.com/index.php?page=security-notices
CERT

VU#767506 - HTTP/2 implementations are vulnerable to "MadeYouReset" DoS attack through HTTP/2 control frames

https://kb.cert.org/vuls/id/767506
Web page

[CVE-2025-8671] DNS over HTTPs (DoH) DDoS using MadeYouReset HTTP/2 Vulnerability (#5325) · Issues · ISC Open Source Projects / BIND · GitLab

https://gitlab.isc.org/isc-projects/bind9/-/issues/5325
GitHub advisoryMentions a patch (unverified)

HTTP/2 MadeYouReset DDoS vulnerability · Advisory · h2o/h2o · GitHub

Affected: 2023.

https://github.com/h2o/h2o/security/advisories/GHSA-mrjm-qq9m-9mjq
GitHub commit

commit 4729b661e3c6 (h2o/h2o)

Fix landed in h2o/h2o commit 4729b661e3c6 — awaiting tagged release

https://github.com/h2o/h2o/commit/4729b661e3c6654198d2cc62997e1af58bef4b80
Web page

MadeYouReset | Gal Bar Nahum's Blog

https://galbarnahum.com/made-you-reset

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntudnsdist (1.6.1-1ubuntu0.1~esm2) @ jammy2026-10-25ubuntu

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(19 across 14 ecosystems)
Alpine:v3.22(2)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
varnish—
  • every version up to 7.7.2-r0: fixed in 7.7.2-r0
—
Alpine:v3.23(2)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
varnish—
  • every version up to 7.7.2-r0: fixed in 7.7.2-r0
—
Alpine:v3.24(2)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
varnish—
  • every version up to 7.7.2-r0: fixed in 7.7.2-r0
—
Debian:11(2)
PackageVulnerable rangeFix by version rangeDependents
h2o2.2.5+dfsg2-10 ... 2.2.5+dfsg2-9 (10 versions)
  • every version on: no fix on record
—
varnish6.5.1-1 ... 7.7.3-3 (30 versions)
  • every version on: no fix on record
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
h2o2.2.5+dfsg2-10 ... 2.2.5+dfsg2-9 (7 versions)
  • every version on: no fix on record
—
varnish7.1.1-1.1 ... 7.7.3-3 (20 versions)
  • every version on: no fix on record
—
Alpine:v3.15(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
Alpine:v3.16(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
Alpine:v3.17(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
Alpine:v3.18(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
Alpine:v3.19(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
Alpine:v3.20(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
Alpine:v3.21(1)
PackageVulnerable rangeFix by version rangeDependents
lighttpd—
  • every version up to 0-r0: fixed in 0-r0
—
crates.io(1)
PackageVulnerable rangeFix by version rangeDependents
pingora-core—
  • 0.0.0-0 up to 0.6.0: fixed in 0.6.0
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
varnish7.7.0-3
  • every version up to 7.7.0-3+deb13u1: fixed in 7.7.0-3+deb13u1
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 8× in last 7d / 44× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 100 of 219 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 119 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 16:33 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  2. 2026-10-31 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  3. 2026-10-31 12:10 UTCEG score recompute
  4. 2026-10-30 16:33 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  5. 2026-10-29 16:32 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  6. 2026-10-28 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  7. 2026-10-27 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  8. 2026-10-26 16:30 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  9. 2026-10-25 16:32 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  10. 2026-10-25 16:00 UTCEG score recompute
  11. 2026-10-25 02:31 UTCEG score recompute
  12. 2026-10-25 02:31 UTCVendor advisory
  13. 2026-10-24 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  14. 2026-10-23 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  15. 2026-10-22 16:33 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  16. 2026-10-21 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  17. 2026-10-20 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  18. 2026-10-19 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  19. 2026-10-18 16:52 UTCEG score recompute
  20. 2026-10-18 16:52 UTCVendor advisory
  21. 2026-10-18 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  22. 2026-10-18 05:14 UTCEG score recompute
  23. 2026-10-17 21:18 UTCEG score recompute
  24. 2026-10-17 21:18 UTCVendor advisory
  25. 2026-10-17 16:33 UTCEPSS rescoreEPSS 3.6% · 89th percentile
Show 75 more
  1. 2026-10-16 16:40 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  2. 2026-10-15 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  3. 2026-10-14 16:31 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  4. 2026-10-13 16:33 UTCEPSS rescoreEPSS 3.6% · 89th percentile
  5. 2026-10-12 16:44 UTCEG score recompute
  6. 2026-10-12 16:33 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  7. 2026-10-11 20:18 UTCEG score recompute
  8. 2026-10-11 18:31 UTCEG score recompute
  9. 2026-10-11 15:05 UTCEG score recompute
  10. 2026-10-11 13:47 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  11. 2026-10-10 19:59 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  12. 2026-10-09 20:06 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  13. 2026-10-08 17:11 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  14. 2026-10-07 23:47 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  15. 2026-10-06 15:38 UTCOSV refresh
  16. 2026-10-06 15:17 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  17. 2026-10-05 17:42 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  18. 2026-10-04 23:21 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  19. 2026-10-03 14:25 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  20. 2026-10-01 19:49 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  21. 2026-09-30 15:02 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  22. 2026-09-29 15:20 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  23. 2026-09-28 13:50 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  24. 2026-09-26 15:58 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  25. 2026-09-23 13:47 UTCEPSS rescoreEPSS 3.7% · 89th percentile
  26. 2026-09-18 19:27 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  27. 2026-09-16 20:20 UTCOSV refresh
  28. 2026-09-16 14:07 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  29. 2026-09-16 05:14 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  30. 2026-09-15 03:10 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  31. 2026-09-13 16:46 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  32. 2026-09-12 15:00 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  33. 2026-09-11 14:52 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  34. 2026-09-11 09:36 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  35. 2026-09-10 09:34 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  36. 2026-09-08 22:00 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  37. 2026-09-07 16:00 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  38. 2026-09-06 13:47 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  39. 2026-09-04 05:06 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  40. 2026-09-02 14:11 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  41. 2026-09-01 13:53 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  42. 2026-08-30 01:21 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  43. 2026-08-28 21:40 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  44. 2026-08-28 20:53 UTCOSV refresh
  45. 2026-08-27 14:24 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  46. 2026-08-26 14:45 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  47. 2026-08-25 13:48 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  48. 2026-08-24 14:16 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  49. 2026-08-23 00:18 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  50. 2026-08-21 23:48 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  51. 2026-08-20 22:55 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  52. 2026-08-19 17:03 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  53. 2026-08-18 13:48 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  54. 2026-08-17 13:46 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  55. 2026-08-16 14:55 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  56. 2026-08-16 02:14 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  57. 2026-08-15 01:30 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  58. 2026-08-13 22:00 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  59. 2026-08-12 13:50 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  60. 2026-08-12 08:17 UTCOSV refresh
  61. 2026-08-11 13:42 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  62. 2026-08-10 23:59 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  63. 2026-08-09 13:46 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  64. 2026-08-08 16:36 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  65. 2026-08-07 16:27 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  66. 2026-08-06 13:46 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  67. 2026-08-05 19:17 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  68. 2026-08-04 10:37 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  69. 2026-08-03 10:35 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  70. 2026-08-02 02:26 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  71. 2026-08-01 04:15 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  72. 2026-07-30 16:27 UTCEPSS rescoreEPSS 3.5% · 88th percentile
  73. 2026-07-30 01:30 UTCEPSS rescoreEPSS 3.5% · 87th percentile
  74. 2026-07-27 15:27 UTCOSV refresh
  75. 2026-07-27 14:13 UTCEPSS rescoreEPSS 3.5% · 87th percentile

Publicly available exploits

(3 references)

Public exploit code is referenced for this CVE (2 GitHub PoCs), as is 1 GitHub checker repository. A GitHub repository named or described as a checker or scanner checks whether a system is affected; it is not necessarily exploit code. Defenders should treat patch urgency accordingly.

  • GitHub checkerayushghatkar8080/MadeYouReset_Tester
    Published Jun 1, 2026

    A Python script that checks if a web server is vulnerable to MadeYouReset (CVE-2025-8671) — an HTTP/2 DoS attack that bypasses Rapid Reset mitigations by tricking the server into resetting its own streams. It probes the target by sending a malformed WINDOW_UPDATE frame and inspects whether the server responds.

    Open source ↗
  • GitHub PoCmateusm1403/PoC-CVE-2025-8671-MadeYouReset-HTTP-2
    Published Aug 21, 2025

    PoC para validar vulnerabilidade MadeYouReset

    Open source ↗
  • GitHub PoCmoften/CVE-2025-8671-MadeYouReset-HTTP-2-DDoS
    Published Aug 18, 2025

    CVE-2025-25063 MadeYouReset HTTP/2 DDoS

    Open source ↗

Frequently asked(5)

What is CVE-2025-8671?
CVE-2025-8671 is a high-severity vulnerability; its CVE record was published on August 13, 2025. 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…
When was the CVE record for CVE-2025-8671 published?
The CVE record for CVE-2025-8671 was published on August 13, 2025. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of June 17, 2026; the record at its source may have been updated since.
Is CVE-2025-8671 actively exploited?
CVE-2025-8671 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 3.6% probability of exploitation in the next 30 days (89th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2025-8671?
CVE-2025-8671 has a CVSS v3.1 base score of 7.5 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2025-8671?
A fix for CVE-2025-8671 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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