CVE-2026-100725
http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage
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.
- Record
CVE-2026-100725- CVSS 4.0
- 8.3 High
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 - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N - Weakness
- CWE-200
- Updated
- 2026-11-02
EUVDEUVD-2026-87854
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.
- Record
EUVD-2026-87854- CVSS 4.0
- 8.3 High
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 - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-jggj-q26h-3m3c
http4k (Maven artifact org.http4k:http4k-core) before 6.48.0.0, 5.42.0.0, and 4.51.0.0 ships a...
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.
- Record
GHSA-jggj-q26h-3m3c- CVSS 4.0
- 8.3 High
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 - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N - Weakness
- CWE-200
- Updated
- 2026-11-02
GitHub AdvisoriesGHSA-pr33-38xx-6r26
http4k: BasicCookieStorage` (renamed `InsecureCookieStorage`) did not enforce RFC 6265 cookie scoping; new `DefaultCookieStorage` is now the default
Impact
The previous BasicCookieStorage did not enforce RFC 6265 scoping rules around cookie domain, path, and Secure attribute. A client using a single storage instance to talk to multiple origins could have cookies leak across domains, or have Secure cookies sent over plain HTTP — the deprecation message states it bluntly: "BasicCookieStorage has no domain/path/scheme scoping and leaks cookies across origins. Use DefaultCookieStorage instead."
Who is affected: any client using BasicCookieStorage directly with cookies for more than one origin or scheme. Single-origin uses are unaffected.
Patches
| Line | Fixed in | Edition | |------|----------|---------| | v6.x (Community) | 6.48.0.0 | Community | | v5.x (LTS) | 5.42.0.0 | Enterprise — contact [email protected] | | v4.x (LTS) | 4.51.0.0 | Enterprise — contact [email protected] |
The fix introduces DefaultCookieStorage (RFC 6265 compliant) as the drop-in default; BasicCookieStorage is renamed InsecureCookieStorage and remains available for callers with a deliberate need for the old behaviour.
Workarounds
For deployments that cannot upgrade immediately:
- Use a dedicated
BasicCookieStorageinstance per origin / scheme, or - Switch to a separate RFC 6265-compliant cookie store implementation.
References
- Fix release: v6.48.0.0
- Cookie storage rewrite:
6a9b44d743 - Background: RFC 6265 — HTTP State Management Mechanism
- Record
GHSA-pr33-38xx-6r26- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-200
- Updated
- 2026-11-02
NVD
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.
- Record
CVE-2026-100725- CVSS 4.0
- 8.3 High
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 - CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N - Weakness
- CWE-200
- Updated
- 2026-11-02
OSV
http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage
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.
- Record
CVE-2026-100725- CVSS 4.0
- 8.3 High
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 - Weakness
- CWE-200
- Updated
- 2026-11-02
OSVGHSA-pr33-38xx-6r26
http4k: BasicCookieStorage` (renamed `InsecureCookieStorage`) did not enforce RFC 6265 cookie scoping; new `DefaultCookieStorage` is now the default
Impact
The previous BasicCookieStorage did not enforce RFC 6265 scoping rules around cookie domain, path, and Secure attribute. A client using a single storage instance to talk to multiple origins could have cookies leak across domains, or have Secure cookies sent over plain HTTP — the deprecation message states it bluntly: "BasicCookieStorage has no domain/path/scheme scoping and leaks cookies across origins. Use DefaultCookieStorage instead."
Who is affected: any client using BasicCookieStorage directly with cookies for more than one origin or scheme. Single-origin uses are unaffected.
Patches
| Line | Fixed in | Edition | |------|----------|---------| | v6.x (Community) | 6.48.0.0 | Community | | v5.x (LTS) | 5.42.0.0 | Enterprise — contact [email protected] | | v4.x (LTS) | 4.51.0.0 | Enterprise — contact [email protected] |
The fix introduces DefaultCookieStorage (RFC 6265 compliant) as the drop-in default; BasicCookieStorage is renamed InsecureCookieStorage and remains available for callers with a deliberate need for the old behaviour.
Workarounds
For deployments that cannot upgrade immediately:
- Use a dedicated
BasicCookieStorageinstance per origin / scheme, or - Switch to a separate RFC 6265-compliant cookie store implementation.
References
- Fix release: v6.48.0.0
- Cookie storage rewrite:
6a9b44d743 - Background: RFC 6265 — HTTP State Management Mechanism
- Record
GHSA-pr33-38xx-6r26- CVSS 4.0
- 6.9 Medium
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N - Weakness
- CWE-200
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.http4k:http4k-coreMaven |
6.0.0.0 up to 6.48.0.0 | 6.48.0.0 |
org.http4k:http4k-coreMaven |
5.0.0.0 up to 5.42.0.0 | 5.42.0.0 |
org.http4k:http4k-coreMaven |
before 4.51.0.0 | 4.51.0.0 |
org.http4k:http4k-coreMaven |
6.0.0.0 up to 6.48.0.0, plus listed versions 6.0.1.06.1.0.06.1.0.16.10.0.06.10.1.0 Show 45 moreShow less6.10.2.06.11.0.06.11.1.06.12.0.06.13.0.06.14.0.06.15.0.06.15.0.16.15.1.06.16.0.06.17.0.06.18.0.16.18.1.06.19.0.06.2.0.06.20.0.06.20.0.16.20.0.26.20.0.36.20.1.06.20.2.06.20.2.16.21.0.06.21.1.06.22.0.06.23.0.06.23.1.06.24.0.06.24.1.06.25.0.06.25.1.06.26.0.06.26.1.06.27.0.06.28.0.06.28.1.06.29.0.06.30.0.06.30.1.06.31.0.06.31.1.06.32.0.06.33.0.06.34.0.06.35.0.0 |
6.48.0.0 |
org.http4k:http4k-coreMaven |
5.0.0.0 up to 5.42.0.0, plus listed versions 5.1.0.05.1.1.05.1.1.15.1.2.05.1.2.1 Show 45 moreShow less5.10.0.05.10.1.05.10.2.05.10.3.05.10.4.05.10.5.05.10.6.05.10.7.05.11.0.05.11.1.05.12.0.05.12.1.05.12.2.05.12.2.15.13.0.05.13.0.15.13.1.05.13.2.05.13.4.05.13.4.15.13.5.05.13.6.05.13.6.15.13.7.05.13.8.05.13.9.05.14.0.05.14.1.05.14.2.05.14.4.05.14.5.05.15.0.05.16.0.05.16.1.05.16.2.05.17.0.05.18.1.05.18.2.05.19.0.05.2.0.05.2.1.05.20.0.05.21.0.05.21.1.05.21.2.0 |
5.42.0.0 |
org.http4k:http4k-coreMaven |
before 4.51.0.0, plus listed versions 0.21.00.22.01.0.01.1.01.10.0 Show 45 moreShow less1.11.01.13.01.14.01.15.01.16.01.17.01.18.01.19.01.19.11.2.01.20.01.21.01.21.11.22.01.22.21.23.01.24.01.25.01.25.11.26.01.26.11.26.21.27.01.28.01.3.01.30.01.31.01.32.01.32.11.32.21.33.01.33.11.4.01.5.01.6.01.7.01.8.01.9.02.0.02.0.12.0.22.0.32.0.42.0.52.1.0 |
4.51.0.0 |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-100725 is a high vulnerability (CVSS 8.3) in Http4k, published June 19, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.24%, the 15th percentile. Fixed in org.http4k:http4k-core 6.48.0.0.
References
github.com/http4k/http4k/security/advisories/GHSA-pr33-38xx-6r26
vulncheck.com/advisories/http4k-before-6.48.0.0-cookie-scoping-bypass-via-basiccookiestorage
nvd.nist.gov/vuln/detail/CVE-2026-100725
datatracker.ietf.org/doc/html/rfc6265
Left out here: 659 versions. The JSON record has them.