CVE-2026-100725
http4k before 6.48.0.0 Cookie Scoping Bypass via BasicCookieStorage
No known exploitation. EPSS puts it in the 15th percentile. Fixed in 6.48.0.0.
No public exploit knownFix6.48.0.0Upgrade to this build
No ready-made check. Neither Nuclei nor OpenVAS has one for this CVE yet.
What to do
Find your product and version, then upgrade to the build on the right.
- Http4kAffected: ≥ 6.0.0.0, < 6.48.0.0Upgrade to: 6.48.0.0Stated by: CVE record
Versions as the sources state them. Full version matrix after sign-in
What it is
From the CVE record
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.
In plain language
No plain-language summary for this CVE yet.
Exploitation
Where each signal puts this CVE on the scale from published to confirmed exploited.
- CISA KEV
Not in the catalog. CISA has not confirmed exploitation.
- Public exploits
No public exploit or proof of concept found in the sources we track.
- EPSS
0.2% chance of exploitation activity in the next 30 days, which ranks it in the 15th percentile of scored CVEs.
Exploit Prediction Scoring System, FIRST.org. A probability, not a confirmation.
Lifecycle
7 events over 32 days, from the signal feeds we watch.
- Record updated
- Record updated
- Record updated
- Publishedweakness classified, att&ck mapped, record updated
Affected products
Technical detail
CVSS 3.1 vector
Open in the CVSS calculatorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Scored 6.5 by NVD.
How it is reached
- Attack Vector NetworkExploitable remotely over the network without any special conditions
- Attack Complexity HighRequires specific conditions like a race condition or non-default configuration
- Privileges Required NoneNo authentication required — anyone can exploit this
- User Interaction NoneNo user interaction needed — fully automated exploitation
Scope
- Scope UnchangedImpact is limited to the vulnerable component itself
Impact if exploited
- Confidentiality HighTotal information disclosure — all data in the component is compromised
- Integrity LowData modification is possible but limited in scope or consequence
- Availability NoneNo availability impact
Weaknesses
ATT&CK techniques
Mapped from the weaknesses above (CWE to ATT&CK), not observed in attacks.
Sources
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