cbcvebase.
CVE-2009-2698
published 2009-08-27

CVE-2009-2698: The udp_sendmsg function in the UDP implementation in (1) net/ipv4/udp.c and (2) net/ipv6/udp.c in the Linux kernel before 2.6.19 allows local users to gain…

PriorityP271high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
ITWEXPLOITVulnCheck KEV
Exploited in the wild
EPSS
7.12%
93.5th percentile
The udp_sendmsg function in the UDP implementation in (1) net/ipv4/udp.c and (2) net/ipv6/udp.c in the Linux kernel before 2.6.19 allows local users to gain privileges or cause a denial of service (NULL pointer dereference and system crash) via vectors involving the MSG_MORE flag and a UDP socket.

Affected

25 ranges
VendorProductVersion rangeFixed in
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
canonicalubuntu_linux
fedoraprojectfedora
linuxlinux_kernel< 2.6.192.6.19
redhatenterprise_linux_desktop
redhatenterprise_linux_desktop
redhatenterprise_linux_eus
redhatenterprise_linux_eus
redhatenterprise_linux_server
redhatenterprise_linux_server
redhatenterprise_linux_server_aus
redhatenterprise_linux_workstation
redhatenterprise_linux_workstation
suselinux_enterprise_desktop
suselinux_enterprise_server
suselinux_enterprise_server
vmwareesxi
vmwareesxi
vmwarevcenter_server
vmwarevmware_tools
vmwarevmware_vcenter_server
vmwarevmware_vsphere
vmwarevmware_workstation

Detection & IOCsextracted from sources · hover to see the quote

urlhttp://grsecurity.net/~spender/therebel.tgz
urlhttps://gitlab.com/exploit-database/exploitdb-bin-sploits/-/raw/main/bin-sploits/9574.tgz
hash656fddc1bf4743a08a455628b6151076b81e604ff49c93d797fa49b1f7d09c2f
commandsendto(fd,buf,1024,MSG_PROXY|MSG_MORE,&x0x,sizeof(x0x));
commandsendmsg(s, &header, MSG_MORE|MSG_PROXY);
pathnet/ipv4/udp.c
pathnet/ipv6/udp.c
yara
rule Linux_Exploit_CVE_2009_2698_12374e97 {
    meta:
        author = "Elastic Security"
        id = "12374e97-385e-4b3a-9d50-39f35ad4f6dd"
        fingerprint = "2c669220ac8909e2336bbf9c38489c8e32d573ab6c29fa1e2e0c1fe69f7441ed"
        creation_date = "2021-01-12"
        last_modified = "2021-09-16"
        threat_name = "Linux.Exploit.CVE-2009-2698"
        reference_sample = "656fddc1bf4743a08a455628b6151076b81e604ff49c93d797fa49b1f7d09c2f"
        severity = 100
        arch_context = "x86"
        scan_context = "file, memory"
        license = "Elastic License v2"
        os = "linux"
    strings:
        $a = { 74 64 6F 75 74 00 66 77 72 69 74 65 00 64 65 73 63 00 63 76 65 00 }
    condition:
        all of them
}
bytes
74 64 6F 75 74 00 66 77 72 69 74 65 00 64 65 73 63 00 63 76 65 00
  • Exploit maps a page at virtual address 0x0 (NULL page) with PROT_READ|PROT_WRITE|PROT_EXEC using mmap(MAP_FIXED) or mprotect, then places shellcode/callback pointer there to achieve kernel code execution.
  • Exploit writes a function pointer at offset 0x74 of the mmap'd NULL page to hijack the dst_entry->output callback, which is invoked in kernel context.
  • Exploit uses AF_UNSPEC socket family with sa_data filled with 0x82 bytes as the destination address in the triggering sendto call.
  • Privilege escalation is confirmed by checking getuid() after the exploit; if still non-zero, the exploit failed. Success results in execl('/bin/sh') spawning a root shell.
  • YARA rule targets the exploit binary in both file and memory scan contexts on Linux x86, matching the byte string { 74 64 6F 75 74 00 66 77 72 69 74 65 00 64 65 73 63 00 63 76 65 00 }.
  • ·The vulnerability only affects Linux kernels before 2.6.19; patched or newer kernels are not affected.
  • ·Red Hat Enterprise MRG kernel versions were not affected by this issue.
  • ·The exploit (9542) requires the calling process to be non-root (uid != 0) to proceed; it checks uid at start and aborts if already root.
  • ·The exploit (9542) handles two personality cases: PER_SVR4 uses mprotect on address 0, while all other personalities use mmap MAP_FIXED at address 0 to map the NULL page.

CVSS provenance

nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
nvdv2.07.2HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
vulncheck7.8HIGH
vendor_redhat7.8HIGH
vendor_ubuntu4.4MEDIUM
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