CVE-2026-69203

HIGHPre-NVD 7.57.5—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 7.5 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.5%, top 61% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, secondary
Trending — 3 sources updated this week
7.5EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 7.5Exploit: None knownExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, An Ember server with HTTP/2 enabled through withHttp2 does not enforce SETTINGS_MAX_CONCURRENT_STREAMS for peer-created streams. One unauthenticated connection can open an unbounded number of streams, each retaining per-stream state until heap exhaustion. The same unchecked allocation is reachable in an ember-client through server-initiated PUSH_PROMISE frames because enablePush is not enforced. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVSS v3
7.5
EG Score
7.5(medium)
EG Risk
49(Track)
EG Risk 49/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity75% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
39%
KEV
Not listed

Published

September 15, 2026

Last Modified

September 16, 2026

Advisory Details (4)

Auto-updated Sep 15, 2026
Patch available. Sources: github_release, github, github_commit.
github_release Patch Available

v1.0.0-M47

Patch available: http4s/http4s v1.0.0-M47 (pre-release)

https://github.com/http4s/http4s/releases/tag/v1.0.0-M47
github_release Patch Available

v0.23.35

Patch available: http4s/http4s v0.23.35

https://github.com/http4s/http4s/releases/tag/v0.23.35
github_commit Patch Available

commit 4983de1f93f2 (http4s/http4s)

Patch available: http4s/http4s v0.23.35 (contains commit 4983de1f93f2)

https://github.com/http4s/http4s/commit/4983de1f93f2caaa3b9de310cf6a9db32c50d66e
github Patch Available

Ember HTTP/2: does not enforce SETTINGS_MAX_CONCURRENT_STREAMS · Advisory · http4s/http4s · GitHub

https://github.com/http4s/http4s/security/advisories/GHSA-9vwc-pc8p-253q

Vendor Advisories for CVE-2026-69203(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Affected Packages

(3 across 1 ecosystem)
Maven(3)
PackageVulnerable rangeFixed inDependents
org.http4s:http4s-ember-core_2.120.10.0-M10 ... 0.23.9 (114 versions)0.23.35—
org.http4s:http4s-ember-core_2.130.10.0-M10 ... 0.23.9 (114 versions)0.23.35—
org.http4s:http4s-ember-core_30.22.0 ... 0.23.9 (58 versions)0.23.35—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 9× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.

  1. 2026-09-19 06:06 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-17 19:54 UTCEG score recompute
  4. 2026-09-16 20:11 UTCEG score recompute
  5. 2026-09-16 14:08 UTCEPSS rescore
  6. 2026-09-15 20:40 UTCEG score recompute
  7. 2026-09-15 19:43 UTCEG score recompute
  8. 2026-09-15 19:23 UTCEG score recompute
  9. 2026-09-15 19:22 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-69203?
CVE-2026-69203 is a high vulnerability published on September 15, 2026. Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, An Ember server with HTTP/2 enabled through withHttp2 does not enforce SETTINGSMAXCONCURRENTSTREAMS for peer-created streams. One unauthenticated connection can open an unbounded number of streams, each retaining…
When was CVE-2026-69203 disclosed?
CVE-2026-69203 was first published in the National Vulnerability Database on September 15, 2026, with the most recent update on September 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-69203 actively exploited?
CVE-2026-69203 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 60.9% of all scored CVEs.
What is the CVSS score of CVE-2026-69203?
CVE-2026-69203 has a CVSS v3 base score of 7.5 (NVD).
How do I remediate CVE-2026-69203?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-69203, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2026-69203

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