Back to CVE records
Medium 4.8Published Sep 15, 2026

CVE-2026-69211Http4s: Set-Cookie rendering does not escape attribute delimiters

Updated under an hour ago ()

Does this affect you?

It affects http4s. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, ResponseCookie.render writes attacker-influenced name, content, domain, path, and extension values without neutralizing semicolons or control characters. An application that constructs a ResponseCookie from unvalidated input can therefore emit injected cookie attributes such as Domain, Path, or SameSite, widening cookie scope or weakening protections, and control characters may enable header splitting on permissive backends. The patch strips control characters from all five fields and strips semicolons from name, content, domain, and path while retaining the extension delimiter behavior. This issue is fixed in versions 0.23.35 and 1.0.0-M47.

CVSS
4.8 MEDIUM (v3.1, CNA)CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Weakness (CWE)
CWE-113, CWE-1286
Known exploited
Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days)
Not loaded for this CVE
Assigned by
GitHub_M
NVD analysis
Deferred
Record last updated
Sep 16, 2026
First seen by InfoSec Signals
Oct 9, 2026

Affected products

Affected products
http4s http4s
http4s:http4s (from the name)
before 0.23.35; from 1.0.0-M1, < 1.0.0-M47
CNA record

References

  • x-refsource-confirm
  • x-refsource-misc
  • x-refsource-misc
  • x-refsource-misc

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.

Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.