#VU12799 Heap-based buffer overflow in cURL - CVE-2018-1000300

Vulnerability identifier: #VU12799

Vulnerability risk: High

CVSSv4.0: 8.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/U:Amber]

CVE-ID: CVE-2018-1000300

CWE-ID: CWE-122

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
cURL
Client/Desktop applications / Other client software

Vendor:
curl.haxx.se

Description
The vulnerability allows a remote attacker to execute arbitrary code on the target system.

The weakness exists due to heap-based buffer overflow when closing down an FTP connection with very long server command replies. When doing FTP transfers, curl keeps a spare "closure handle" around internally that will be used when an FTP connection gets shut down since the original curl easy handle is then already removed. FTP server response data that gets cached from the original transfer might then be larger than the default buffer size (16 KB) allocated in the "closure handle", which can lead to buffer overwrite. A remote attacker can execute arbitrary code.

Successful exploitation of the vulnerability may result in system compromise.

Mitigation
Update to version 7.60.0.

Vulnerable software versions

cURL: 7.54.1 - 7.59.0

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External links
https://curl.haxx.se/docs/adv_2018-82c2.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.