#VU67714 Information disclosure in Apache Tomcat - CVE-2021-43980

Vulnerability identifier: #VU67714

Vulnerability risk: Low

CVSSv4.0: 1.7 [CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2021-43980

CWE-ID: CWE-200

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache Tomcat
Server applications / Web servers

Vendor: Apache Foundation

Description

The vulnerability allows a remote attacker to gain access to potentially sensitive information.

The vulnerability exists due to incorrect implementation of blocking reads and writes. A remote attacker can trigger a concurrency bug and force client connections to share an Http11Processor instance resulting in responses, or part responses, to be received by the wrong client.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Apache Tomcat: 8.5.0 - 8.5.77, 9.0.0-M1 - 9.0.60, 10.0.0-M1 - 10.0.18, 10.1.0-M1 - 10.1.0-M12

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External links
https://lists.apache.org/thread/3jjqbsp6j88b198x5rmg99b1qr8ht3g3

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the Internet.

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.