#VU43989 Input validation error in Linux kernel - CVE-2012-2375

Vulnerability identifier: #VU43989

Vulnerability risk: Medium

CVSSv4.0: 2.3 [CVSS:4.0/AV:A/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2012-2375

CWE-ID: CWE-20

Exploitation vector: Local network

Exploit availability: No

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

Vendor: Linux Foundation

Description

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

The __nfs4_get_acl_uncached function in fs/nfs/nfs4proc.c in the NFSv4 implementation in the Linux kernel before 3.3.2 uses an incorrect length variable during a copy operation, which allows remote NFS servers to cause a denial of service (OOPS) by sending an excessive number of bitmap words in an FATTR4_ACL reply. NOTE: this vulnerability exists because of an incomplete fix for CVE-2011-4131.

Mitigation
Install update from vendor's website.

Vulnerable software versions

Linux kernel: 3.3

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External links
https://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=20e0fa98b751facf9a1101edaefbc19c82616a68
https://marc.info/?l=bugtraq&m=139447903326211&w=2
https://rhn.redhat.com/errata/RHSA-2012-1580.html
https://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.3.2
https://www.openwall.com/lists/oss-security/2012/05/18/13
https://bugzilla.redhat.com/show_bug.cgi?id=822869
https://github.com/torvalds/linux/commit/20e0fa98b751facf9a1101edaefbc19c82616a68

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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 local network (LAN).

Is there known malware, which exploits this vulnerability?

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