GNOME libsoup Cookie Expiration Date integer overflow

Summaryinfo

A vulnerability marked as critical has been reported in GNOME libsoup. This affects an unknown function of the component Cookie Expiration Date Handler. Performing a manipulation results in integer overflow. This vulnerability is reported as CVE-2025-4945. The attack is possible to be carried out remotely. No exploit exists.

Detailsinfo

A vulnerability classified as critical has been found in GNOME libsoup (the affected version is unknown). This affects an unknown code of the component Cookie Expiration Date Handler. The manipulation with an unknown input leads to a integer overflow vulnerability. CWE is classifying the issue as CWE-190. The product performs a calculation that can produce an integer overflow or wraparound, when the logic assumes that the resulting value will always be larger than the original value. This can introduce other weaknesses when the calculation is used for resource management or execution control. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

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.

The advisory is shared at bugzilla.redhat.com. This vulnerability is uniquely identified as CVE-2025-4945 since 05/19/2025. The exploitability is told to be easy. It is possible to initiate the attack remotely. Neither technical details nor an exploit are publicly available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 01/07/2026).

The vulnerability scanner Nessus provides a plugin with the ID 237944 (Fedora 42 : mingw-libsoup (2025-c04e5b95f1)), which helps to determine the existence of the flaw in a target environment.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the databases at Tenable (237944), EUVD (EUVD-2025-16034) and CERT Bund (WID-SEC-2025-2488). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Affected

• Debian Linux
• Red Hat Enterprise Linux
• SUSE Linux
• Oracle Linux
• RESF Rocky Linux
• Xerox FreeFlow Print Server
• Red Hat OpenShift

Productinfo

Vendor

• GNOME

Name

• libsoup

License

• open-source

Website

• Vendor: https://www.gnome.org/

CPE 2.3info

• 🔍

CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion