HTTP Response Splitting Affecting langfuse-3 package, versions <3.164.0-r5


Severity

Recommended
0.0
medium
0
10

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Threat Intelligence

EPSS
0.42% (35th percentile)

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  • Snyk IDSNYK-CHAINGUARDLATEST-LANGFUSE3-20145262
  • published26 Sept 2026
  • disclosed23 Jun 2026

Introduced: 23 Jun 2026

CVE-2026-56762  (opens in a new tab)
CWE-113  (opens in a new tab)

How to fix?

Upgrade Chainguard langfuse-3 to version 3.164.0-r5 or higher.

NVD Description

Note: Versions mentioned in the description apply only to the upstream langfuse-3 package and not the langfuse-3 package as distributed by Chainguard. See How to fix? for Chainguard relevant fixed versions and status.

Hono before 4.12.12 does not validate cookie names on the write path in the setCookie(), serialize(), and serializeSigned() functions, allowing invalid characters such as control characters (e.g. \r or \n) when an application passes a user-controlled cookie name. This can produce malformed Set-Cookie header values. In modern runtimes such as Node.js and Cloudflare Workers, such invalid header values are rejected and cause a runtime error before the response is sent, so header injection or response splitting could not be reproduced; the issue primarily affects correctness and robustness, resulting in runtime errors (availability) rather than confirmed header injection.

CVSS Base Scores

version 3.1