CVE-2023-4639: Request Smuggling (CVSS 7.4)

Description

A flaw was found in Undertow, which incorrectly parses cookies with certain value-delimiting characters in incoming requests. This issue could allow an attacker to construct a cookie value to exfiltrate HttpOnly cookie values or spoof arbitrary additional cookie values, leading to unauthorized data access or modification. The main threat from this flaw impacts data confidentiality and integrity.

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CVSS v3.1 Score

7.4

HIGH

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N

Weakness Type (CWE)

CWE-444 CWE-444

References

Other References

https://access.redhat.com/errata/RHSA-2024:1674 https://access.redhat.com/errata/RHSA-2024:1675 https://access.redhat.com/errata/RHSA-2024:1676 https://access.redhat.com/errata/RHSA-2024:1677 https://access.redhat.com/errata/RHSA-2024:2763 https://access.redhat.com/errata/RHSA-2024:2764 https://access.redhat.com/errata/RHSA-2024:3919 https://access.redhat.com/security/cve/CVE-2023-4639 https://bugzilla.redhat.com/show_bug.cgi?id=2166022 https://security.netapp.com/advisory/ntap-20250207-0001/

Frequently Asked Questions

What is CVE-2023-4639? +

A flaw was found in Undertow, which incorrectly parses cookies with certain value-delimiting characters in incoming requests. This issue could allow an attacker to construct a cookie value to exfiltrate HttpOnly cookie values or spoof arbitrary additional cookie values, leading to unauthorized data access or modification. The main threat from this flaw impacts data confidentiality and integrity. It has a CVSS v3.1 base score of 7.4 (HIGH).

How severe is CVE-2023-4639? +

CVE-2023-4639 has a CVSS v3.1 score of 7.4 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

How do I check if I'm vulnerable to CVE-2023-4639? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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CVE-2023-4639