Summary
A cookie is set using the secure keyword for https://target curl is redirected to or...
- A cookie is set using the
securekeyword forhttps://target - curl is redirected to or otherwise made to speak with
http://target(same
hostname, but using clear text HTTP) using the same cookie set - The same cookie name is set - but with just a slash as path (
path='/').
Since this site is not secure, the cookie should just be ignored. - A bug in the path comparison logic makes curl read outside a heap buffer
boundary
The bug either causes a crash or it potentially makes the comparison come to
the wrong conclusion and lets the clear-text site override the contents of the
secure cookie, contrary to expectations and depending on the memory contents
immediately following the single-byte allocation that holds the path.
The presumed and correct behavior would be to plainly ignore the second set of
the cookie since it was already set as secure on a secure host so overriding
it on an insecure host should not be okay.
Impact
A read operation accesses a memory location beyond the intended buffer boundary. Typical impact: sensitive data disclosure or crash.
CVE-2025-9086 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. No fixed version is listed yet, so configuration controls and monitoring matter more in the interim.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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Frequently Asked Questions
- What is CVE-2025-9086? CVE-2025-9086 is a high-severity out-of-bounds read vulnerability. No fixed version is listed yet. A read operation accesses a memory location beyond the intended buffer boundary.
- How severe is CVE-2025-9086? CVE-2025-9086 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
- Is there a fix for CVE-2025-9086? No fixed version is listed for CVE-2025-9086 yet. Monitor the advisory for updates and apply mitigations in the interim.
- Is CVE-2025-9086 exploitable, and should I be worried? Whether CVE-2025-9086 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2025-9086 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.