#VU7518 Use-after-free error in Apache HTTP Server - CVE-2017-9789

Vulnerability identifier: #VU7518

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2017-9789

CWE-ID: CWE-416

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Apache HTTP Server
Server applications / Web servers

Vendor: Apache Foundation

Description
The vulnerability allows a remote unauthenticated attacker to cause DoS condition on the targeted system.

The weakness exists due to use-after-free condition in the mod_http2 function. A remote attacker can trigger memory corruption and cause the server to crash.

Successful exploitation of the vulnerability results in denial of service.

Mitigation
Update to version 2.4.27.

Vulnerable software versions

Apache HTTP Server: 2.4.26

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External links
https://httpd.apache.org/security/vulnerabilities_24.html

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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.