Tomcat 今天又爆出两个新的重要的漏洞，这两个漏洞分别是：

CVE-2011-3375 Apache Tomcat Information disclosure

Severity: Important

Vendor: The Apache Software Foundation

Versions Affected:
- Tomcat 7.0.0 to 7.0.21
- Tomcat 6.0.30 to 6.0.33
- Earlier versions are not affected

Description:
For performance reasons, information parsed from a request is often
cached in two places: the internal request object and the internal
processor object. These objects are not recycled at exactly the same time.
When certain errors occur that needed to be added to the access log, the
access logging process triggers the re-population of the request object
after it has been recycled. However, the request object was not recycled
before being used for the next request. That lead to information leakage
(e.g. remote IP address, HTTP headers) from the previous request to the
next request.
The issue was resolved be ensuring that the request and response objects
were recycled after being re-populated to generate the necessary access
log entries.

解决的办法：
- Tomcat 7.0.x 用户应该升级到 7.0.22 或者更新版本
- Tomcat 6.0.x 应该升级到 6.0.35 或更新版本

CVE-2012-0022 Apache Tomcat Denial of Service

Severity: Important

Vendor: The Apache Software Foundation

Versions Affected:
- Tomcat 7.0.0 to 7.0.22
- Tomcat 6.0.0 to 6.0.33
- Tomcat 5.5.0 to 5.5.34
- Earlier, unsupported versions may also be affected

Description:
Analysis of the recent hash collision vulnerability identified unrelated
inefficiencies with Apache Tomcat's handling of large numbers of
parameters and parameter values. These inefficiencies could allow an
attacker, via a specially crafted request, to cause large amounts of CPU
to be used which in turn could create a denial of service.
The issue was addressed by modifying the Tomcat parameter handling code
to efficiently process large numbers of parameters and parameter values.

Mitigation:
Users of affected versions should apply one of the following mitigations:
- Tomcat 7.0.x users should upgrade to 7.0.23 or later
- Tomcat 6.0.x users should upgrade to 6.0.35 or later
- Tomcat 5.5.x users should upgrade to 5.5.35 or later