CVE-2019-17563

CVE-2019-17563 is a high-severity vulnerability in Apache Tomcat with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 11% places it in the 95th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-384.

Key facts

• Severity: High (CVSS 3.x base score 7.5)
• CVSS v2: 5.1
• EPSS exploit prediction: 11% (95th percentile)
• Actively exploited: Not listed in CISA KEV
• Weakness: CWE-384
• Affected product: Apache Tomcat
• Published: 2019-12-23
• Last modified: 2026-06-17

Description

When using FORM authentication with Apache Tomcat 9.0.0.M1 to 9.0.29, 8.5.0 to 8.5.49 and 7.0.0 to 7.0.98 there was a narrow window where an attacker could perform a session fixation attack. The window was considered too narrow for an exploit to be practical but, erring on the side of caution, this issue has been treated as a security vulnerability.

Frequently asked questions

What is CVE-2019-17563?

When using FORM authentication with Apache Tomcat 9.0.0.M1 to 9.0.29, 8.5.0 to 8.5.49 and 7.0.0 to 7.0.98 there was a narrow window where an attacker could perform a session fixation attack. The window was considered too narrow for an exploit to be practical but, erring on the side of caution, this issue has been treated as a security vulnerability.

How severe is CVE-2019-17563?

CVE-2019-17563 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2019-17563 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 11% (95th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-17563?

CVE-2019-17563 primarily affects Apache Tomcat. In total, 13 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2019-17563?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-17563 published?

CVE-2019-17563 was published on 2019-12-23 and last updated on 2026-06-17.

References

• http://lists.opensuse.org/opensuse-security-announce/2020-01/msg00013.html
• https://lists.apache.org/thread.html/8b4c1db8300117b28a0f3f743c0b9e3f964687a690cdf9662a884bbd%40%3Cannounce.tomcat.apache.org%3E
• https://lists.apache.org/thread.html/r3bbb800a816d0a51eccc5a228c58736960a9fffafa581a225834d97d%40%3Cdev.tomcat.apache.org%3E
• https://lists.apache.org/thread.html/r48c1444845fe15a823e1374674bfc297d5008a5453788099ea14caf0%40%3Cdev.tomcat.apache.org%3E
• https://lists.apache.org/thread.html/r6ccee4e849bc77df0840c7f853f6bd09d426f6741247da2b7429d5d9%40%3Cdev.tomcat.apache.org%3E
• https://lists.apache.org/thread.html/r9136ff5b13e4f1941360b5a309efee2c114a14855578c3a2cbe5d19c%40%3Cdev.tomcat.apache.org%3E
• https://lists.apache.org/thread.html/raba0fabaf4d56d4325ab2aca8814f0b30a237ab83d8106b115ee279a%40%3Cdev.tomcat.apache.org%3E
• https://lists.apache.org/thread.html/reb9a66f176df29b9a832caa95ebd9ffa3284e8f4922ec4fa3ad8eb2e%40%3Cissues.cxf.apache.org%3E
• https://lists.debian.org/debian-lts-announce/2020/01/msg00024.html
• https://lists.debian.org/debian-lts-announce/2020/05/msg00026.html
• https://seclists.org/bugtraq/2019/Dec/43
• https://security.gentoo.org/glsa/202003-43
• https://security.netapp.com/advisory/ntap-20200107-0001/
• https://usn.ubuntu.com/4251-1/
• https://www.debian.org/security/2019/dsa-4596
• https://www.debian.org/security/2020/dsa-4680
• https://www.oracle.com/security-alerts/cpuapr2020.html
• https://www.oracle.com/security-alerts/cpujan2021.html
• https://www.oracle.com/security-alerts/cpujul2020.html

Affected products (13)

• cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
• cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
• cpe:2.3:o:opensuse:leap:15.1:*:*:*:*:*:*:*
• cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
• cpe:2.3:a:oracle:agile_engineering_data_management:6.2.1.0:*:*:*:*:*:*:*
• cpe:2.3:a:oracle:hyperion_infrastructure_technology:11.1.2.4:*:*:*:*:*:*:*
• cpe:2.3:a:oracle:instantis_enterprisetrack:*:*:*:*:*:*:*:*
• cpe:2.3:a:oracle:micros_relate_crm_software:11.4:*:*:*:*:*:*:*
• cpe:2.3:a:oracle:mysql_enterprise_monitor:*:*:*:*:*:*:*:*
• cpe:2.3:a:oracle:retail_order_broker:15.0:*:*:*:*:*:*:*
• cpe:2.3:a:oracle:transportation_management:6.3.7:*:*:*:*:*:*:*

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