CVE-2026-69217: High severity (CVSS 8.7)

Description

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, Ember’s HTTP/1.1 parser accepts differing duplicate Content-Length headers and uses the last value instead of rejecting the message. When an Ember server is behind a keep-alive intermediary that selects a different occurrence, an unauthenticated attacker can create CL.CL request smuggling that bypasses front-end controls, captures a later user’s headers, or poisons a cache. The shared client parser can also misframe responses from a malicious or compromised upstream when the client acts as a proxy for multiple downstream consumers. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVSS 3.1 breakdown

Attack vectorNetwork

Attack complexityHigh

Privileges requiredNone

User interactionNone

ScopeChanged

ConfidentialityHigh

IntegrityHigh

AvailabilityNone

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:N

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

Related CVEs

Recent high-severity vulnerabilities sharing a weakness type.

Frequently asked

Is CVE-2026-69217 being actively exploited?

CVE-2026-69217 is not in the CISA KEV catalog.

How severe is CVE-2026-69217?

CVE-2026-69217 has a CVSS 3.1 base score of 8.7, rated high.

How do I fix CVE-2026-69217?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2026-69217 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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