CVE-2009-1897

Severity: medium (CVSS 6.9 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 1.5% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2009-07-20 · updated 2026-06-16
Weakness: CWE-119

Description

The tun_chr_poll function in drivers/net/tun.c in the tun subsystem in the Linux kernel 2.6.30 and 2.6.30.1, when the -fno-delete-null-pointer-checks gcc option is omitted, allows local users to gain privileges via vectors involving a NULL pointer dereference and an mmap of /dev/net/tun, a different vulnerability than CVE-2009-1894.

Affected products

Linux kernel: 2.6.30, 2.6.30-rc1, 2.6.30-rc2, 2.6.30-rc3, 2.6.30-rc4, 2.6.30-rc5 (+3)

References

http://archives.neohapsis.com/archives/fulldisclosure/2009-07/0241.html
http://archives.neohapsis.com/archives/fulldisclosure/2009-07/0246.html
http://article.gmane.org/gmane.linux.network/124939
http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=3c8a9c63d5fd738c261bd0ceece04d9c8357ca13
http://grsecurity.net/~spender/cheddar_bay.tgz
http://isc.sans.org/diary.html?storyid=6820
http://lkml.org/lkml/2009/7/6/19
http://secunia.com/advisories/35839
http://www.openwall.com/lists/oss-security/2009/07/17/1
http://www.vupen.com/english/advisories/2009/1925
https://bugzilla.redhat.com/show_bug.cgi?id=512284
https://exchange.xforce.ibmcloud.com/vulnerabilities/51803

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