#VU36604 Improper Validation of Array Index in Fedora - CVE-2018-17848

Vulnerability identifier: #VU36604

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-2018-17848

CWE-ID: CWE-129

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Fedora
Operating systems & Components / Operating system

Vendor: Fedoraproject

Description

The vulnerability allows a remote non-authenticated attacker to perform a denial of service (DoS) attack.

The html package (aka x/net/html) through 2018-09-25 in Go mishandles <math><template><mn><b></template>, leading to a "panic: runtime error" (index out of range) in (*insertionModeStack).pop in node.go, called from inHeadIM, during an html.Parse call.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Fedora: 28 - 29

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External links
https://github.com/golang/go/issues/27846
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/LREEWY6KNLHRWFZ7OT4HVLMVVCGGUHON/
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UKRCI7WIOCOCD3H7NXWRGIRABTQOZOBK/

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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.