#VU95652 Security restrictions bypass in Linux kernel - CVE-2004-2536

Vulnerability identifier: #VU95652

Vulnerability risk: Low

CVSSv4.0: 2.7 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:U/U:Clear]

CVE-ID: CVE-2004-2536

CWE-ID: CWE-264

Exploitation vector: 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 read and manipulate data.

The exit_thread function (process.c) in Linux kernel 2.6 through 2.6.5 does not invalidate the per-TSS io_bitmap pointers if a process obtains IO access permissions from the ioperm function but does not drop those permissions when it exits, which allows other processes to access the per-TSS pointers, access restricted memory locations, and possibly gain privileges.

Mitigation
Install update from vendor's repository.

Vulnerable software versions

Linux kernel: All versions

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External links
https://secunia.com/advisories/11577
https://www.kernel.org/pub/linux/kernel/v2.6/ChangeLog-2.6.6
https://www.osvdb.org/5997
https://www.securityfocus.com/bid/10302
https://www.ussg.iu.edu/hypermail/linux/kernel/0405.0/1242.html
https://www.ussg.iu.edu/hypermail/linux/kernel/0405.0/1265.html
https://exchange.xforce.ibmcloud.com/vulnerabilities/16106

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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.