CVE-2026-69205

HIGHPre-NVD 8.78.7—
EchelonGraph scoreMEDIUM confidence

This high-severity CVE scores 8.7 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.4%, top 66% 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
8.7EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 8.7Exploit: 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, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunked are incorrectly accepted, and Unicode case folding can turn a Kelvin-sign byte sequence into a match when UTF-8 is used. Intermediaries that apply RFC-compliant token and charset rules can therefore disagree with Ember’s Content-Length or zero-length framing, enabling TE.CL or TE.0 request smuggling, access-control bypass, cross-user request hijacking, and cache poisoning on the server path. Response smuggling through an ember-client gateway requires a malicious or compromised upstream. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVSS v3
8.7
EG Score
8.7(medium)
EG Risk
39(Track)
EG Risk 39/100SSVC: 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
Severity87% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
34%
KEV
Not listed

Published

September 15, 2026

Last Modified

September 16, 2026

Advisory Details (4)

Auto-updated Sep 15, 2026
Patch available. Sources: github, github_commit, github_release.
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 5e88b2e7b4e6 (http4s/http4s)

Patch available: http4s/http4s v0.23.35 (contains commit 5e88b2e7b4e6)

https://github.com/http4s/http4s/commit/5e88b2e7b4e6ea2f0c61040a4bc9de0d73e51217
github Patch Available

Ember Transfer-Encoding value parsing (TE.CL / TE.0 request smuggling) · Advisory · http4s/http4s · GitHub

https://github.com/http4s/http4s/security/advisories/GHSA-9998-894r-fwvr

Vendor Advisories for CVE-2026-69205(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(1)

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 03:50 UTCEG score recompute
  2. 2026-09-18 19:28 UTCEPSS rescore
  3. 2026-09-18 06:09 UTCEG score recompute
  4. 2026-09-16 18:21 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-2026-69205?
CVE-2026-69205 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, Ember’s HeaderP.parse uses a case-sensitive substring test for the Transfer-Encoding value and decodes header bytes with the platform default charset. Values such as Chunked are not recognized, values such as notchunked…
When was CVE-2026-69205 disclosed?
CVE-2026-69205 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-2026-69205 actively exploited?
CVE-2026-69205 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 66.4% of all scored CVEs.
What is the CVSS score of CVE-2026-69205?
CVE-2026-69205 has a CVSS v3 base score of 8.7 (NVD).
How do I remediate CVE-2026-69205?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-69205, 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-2026-69205

Explore →

Is Your Infrastructure Affected by CVE-2026-69205?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs