CVE-2016-9775

CVE-2016-9775 is a high-severity vulnerability in Apache Tomcat with a CVSS 3.x base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-264.

Key facts

Description

The postrm script in the tomcat6 package before 6.0.45+dfsg-1~deb7u3 on Debian wheezy, before 6.0.45+dfsg-1~deb8u1 on Debian jessie, before 6.0.35-1ubuntu3.9 on Ubuntu 12.04 LTS and on Ubuntu 14.04 LTS; the tomcat7 package before 7.0.28-4+deb7u7 on Debian wheezy, before 7.0.56-3+deb8u6 on Debian jessie, before 7.0.52-1ubuntu0.8 on Ubuntu 14.04 LTS, and on Ubuntu 12.04 LTS, 16.04 LTS, and 16.10; and the tomcat8 package before 8.0.14-1+deb8u5 on Debian jessie, before 8.0.32-1ubuntu1.3 on Ubuntu 16.04 LTS, before 8.0.37-1ubuntu0.1 on Ubuntu 16.10, and before 8.0.38-2ubuntu1 on Ubuntu 17.04 might allow local users with access to the tomcat account to gain root privileges via a setgid program in the Catalina directory, as demonstrated by /etc/tomcat8/Catalina/attack.

Frequently asked questions

What is CVE-2016-9775?
The postrm script in the tomcat6 package before 6.0.45+dfsg-1~deb7u3 on Debian wheezy, before 6.0.45+dfsg-1~deb8u1 on Debian jessie, before 6.0.35-1ubuntu3.9 on Ubuntu 12.04 LTS and on Ubuntu 14.04 LTS; the tomcat7 package before 7.0.28-4+deb7u7 on Debian wheezy, before 7.0.56-3+deb8u6 on Debian jessie, before 7.0.52-1ubuntu0.8 on Ubuntu 14.04 LTS, and on Ubuntu 12.04 LTS, 16.04 LTS, and 16.10; and the tomcat8 package before 8.0.14-1+deb8u5 on Debian jessie, before 8.0.32-1ubuntu1.3 on Ubuntu 16.04 LTS, before 8.0.37-1ubuntu0.1 on Ubuntu 16.10, and before 8.0.38-2ubuntu1 on Ubuntu 17.04 might allow local users with access to the tomcat account to gain root privileges via a setgid program in the Catalina directory, as demonstrated by /etc/tomcat8/Catalina/attack.
How severe is CVE-2016-9775?
CVE-2016-9775 has a CVSS 3.x base score of 7.8, rated high severity. It is exploitable over local access with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2016-9775 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2016-9775?
CVE-2016-9775 primarily affects Apache Tomcat. In total, 9 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2016-9775?
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-2016-9775 published?
CVE-2016-9775 was published on 2017-03-23 and last updated on 2026-06-17.

References

Affected products (9)

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