Skip to content
Fencer Vulns
medium 6.5

CVE-2026-100725 json

http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage

published 2026-06-19 4 mo ago modified 2026-10-29 10 d ago also GHSA-pr33-38xx-6r26 , EUVD-2026-87854

cvss
6.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.2%
EPSS 0.2% chance of exploitation in 30 days, percentile 15%
public exploits
0
none known

Summary

http4k (Maven artifact org.http4k:http4k-core) before 6.48.0.0, 5.42.0.0, and 4.51.0.0 ships a BasicCookieStorage (client-side cookie store used by ClientFilters.Cookies) that does not enforce RFC 6265 scoping rules for the cookie domain, path, and Secure attributes. When a single BasicCookieStorage instance is used to talk to more than one origin or scheme, cookies stored for one origin can be sent to other origins, and cookies marked Secure can be sent over plain HTTP, potentially disclosing session cookies or other sensitive values to unauthorized hosts or network observers. Clients that use a storage instance for a single origin are not affected.

Patch / fix

  • maven org.http4k:http4k-core 4.51.0.0, 5.42.0.0, 6.48.0.0
  • http4k http4k 4.51.0.0, 5.42.0.0, 6.48.0.0

Vendor advisories

What the vendors themselves say about their products: affected, fixed or not affected, and what to do.

red hat product security vex CVE-2026-100725 updated cvss 6.5

org.http4k/http4k-core: http4k-core: Sensitive information disclosure via improper cookie scoping

  • Red Hat Fuse 7 http4k-core 4.9.5.0
    affected: workaround, no fix planned “Out of support scope”

Red Hat CSAF VEX © Red Hat, Inc., from https://security.access.redhat.com/data/csaf/v2/vex/; changed: reduced to product statuses and remediations. CC BY 4.0 · csaf

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
41 d ago

Exploit prediction

0.24% chance of exploitation in the next 30 days, higher than 15% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 4.0 8.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N
CNA 3.1 6.5 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
CNA 4.0 8.3 CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:L/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected packages

ecosystem package affected fixed in
maven org.http4k:http4k-core
>=6.0.0.0, <6.48.0.0
>=5.0.0.0, <5.42.0.0
<4.51.0.0
6.48.0.0
5.42.0.0
4.51.0.0

Affected products

  • http4k http4k

Classification

Weakness
  • CWE-200 Exposure of Sensitive Information to an Unauthorized Actor

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.