A flaw was found in the cookie parsing logic of the libsoup HTTP library, used in GNOME applications and other software. The vulnerability arises when processing the expiration date of cookies, where a specially crafted value can trigger an integer overflow. This may result in undefined behavior, allowing an attacker to bypass cookie expiration logic, causing persistent or unintended cookie behavior. The issue stems from improper validation of large integer inputs during date arithmetic operations within the cookie parsing routines.

References

• https://nvd.nist.gov/vuln/detail/CVE-2025-4945
• https://access.redhat.com/security/cve/CVE-2025-4945
• https://bugzilla.redhat.com/show_bug.cgi?id=2367175