#VU51881 Out-of-bounds read in Linux kernel - CVE-2020-25643

Vulnerability identifier: #VU51881

Vulnerability risk: Medium

CVSSv4.0: 4.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-25643

CWE-ID: CWE-125

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Linux kernel
Operating systems & Components / Operating system

Vendor: Linux Foundation

Description

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

The vulnerability exists due to a boundary condition within the HDLC_PPP module of the Linux kernel in the ppp_cp_parse_cr() function. A remote authenticated user can trigger out-of-bounds read error and read contents of memory on the system.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Linux kernel: 5.9 rc1 - 5.9 rc6

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External links
https://lists.opensuse.org/opensuse-security-announce/2020-10/msg00021.html
https://lists.opensuse.org/opensuse-security-announce/2020-10/msg00042.html
https://bugzilla.redhat.com/show_bug.cgi?id=1879981
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=66d42ed8b25b64eb63111a2b8582c5afc8bf1105
https://lists.debian.org/debian-lts-announce/2020/10/msg00028.html
https://lists.debian.org/debian-lts-announce/2020/10/msg00032.html
https://lists.debian.org/debian-lts-announce/2020/10/msg00034.html
https://security.netapp.com/advisory/ntap-20201103-0002/
https://www.debian.org/security/2020/dsa-4774

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated privileged user via the Internet.

Is there known malware, which exploits this vulnerability?

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