CVE-2021-47238

  1. Yack CVE
  2. Vulnerabilities (CVE)
  3. CVE-2021-47238

5.5 /10

CVSS v3 : MEDIUM

V3 Legend

Vector :

Exploitability : 1.8 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

I

n the Linux kernel, the following vulnerability has been resolved: net: ipv4: fix memory leak in ip_mc_add1_src BUG: memory leak unreferenced object 0xffff888101bc4c00 (size 32): comm "syz-executor527", pid 360, jiffies 4294807421 (age 19.329s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 01 00 00 00 00 00 00 00 ac 14 14 bb 00 00 02 00 ................ backtrace: [<00000000f17c5244>] kmalloc include/linux/slab.h:558 [inline] [<00000000f17c5244>] kzalloc include/linux/slab.h:688 [inline] [<00000000f17c5244>] ip_mc_add1_src net/ipv4/igmp.c:1971 [inline] [<00000000f17c5244>] ip_mc_add_src+0x95f/0xdb0 net/ipv4/igmp.c:2095 [<000000001cb99709>] ip_mc_source+0x84c/0xea0 net/ipv4/igmp.c:2416 [<0000000052cf19ed>] do_ip_setsockopt net/ipv4/ip_sockglue.c:1294 [inline] [<0000000052cf19ed>] ip_setsockopt+0x114b/0x30c0 net/ipv4/ip_sockglue.c:1423 [<00000000477edfbc>] raw_setsockopt+0x13d/0x170 net/ipv4/raw.c:857 [<00000000e75ca9bb>] __sys_setsockopt+0x158/0x270 net/socket.c:2117 [<00000000bdb993a8>] __do_sys_setsockopt net/socket.c:2128 [inline] [<00000000bdb993a8>] __se_sys_setsockopt net/socket.c:2125 [inline] [<00000000bdb993a8>] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2125 [<000000006a1ffdbd>] do_syscall_64+0x40/0x80 arch/x86/entry/common.c:47 [<00000000b11467c4>] entry_SYSCALL_64_after_hwframe+0x44/0xae In commit 24803f38a5c0 ("igmp: do not remove igmp souce list info when set link down"), the ip_mc_clear_src() in ip_mc_destroy_dev() was removed, because it was also called in igmpv3_clear_delrec(). Rough callgraph: inetdev_destroy -> ip_mc_destroy_dev -> igmpv3_clear_delrec -> ip_mc_clear_src -> RCU_INIT_POINTER(dev->ip_ptr, NULL) However, ip_mc_clear_src() called in igmpv3_clear_delrec() doesn't release in_dev->mc_list->sources. And RCU_INIT_POINTER() assigns the NULL to dev->ip_ptr. As a result, in_dev cannot be obtained through inetdev_by_index() and then in_dev->mc_list->sources cannot be released by ip_mc_del1_src() in the sock_close. Rough call sequence goes like: sock_close -> __sock_release -> inet_release -> ip_mc_drop_socket -> inetdev_by_index -> ip_mc_leave_src -> ip_mc_del_src -> ip_mc_del1_src So we still need to call ip_mc_clear_src() in ip_mc_destroy_dev() to free in_dev->mc_list->sources.

References
Link Resource
https://git.kernel.org/stable/c/0dc13e75507faa17ac9f7562b4ef7bf8fcd78422 Patch
https://git.kernel.org/stable/c/1e28018b5c83d5073f74a6fb72eabe8370b2f501 Patch
https://git.kernel.org/stable/c/3dd2aeac2e9624cff9fa634710837e4f2e352758 Patch
https://git.kernel.org/stable/c/6cff57eea3347f79f1867cc53e1093b6614138d8 Patch
https://git.kernel.org/stable/c/77de6ee73f54a9a89c0afa0bf4c53b239aa9953a Patch
https://git.kernel.org/stable/c/ac31cc837cafb57a271babad8ccffbf733caa076 Patch
https://git.kernel.org/stable/c/d8e2973029b8b2ce477b564824431f3385c77083 Patch
https://git.kernel.org/stable/c/0dc13e75507faa17ac9f7562b4ef7bf8fcd78422 Patch
https://git.kernel.org/stable/c/1e28018b5c83d5073f74a6fb72eabe8370b2f501 Patch
https://git.kernel.org/stable/c/3dd2aeac2e9624cff9fa634710837e4f2e352758 Patch
https://git.kernel.org/stable/c/6cff57eea3347f79f1867cc53e1093b6614138d8 Patch
https://git.kernel.org/stable/c/77de6ee73f54a9a89c0afa0bf4c53b239aa9953a Patch
https://git.kernel.org/stable/c/ac31cc837cafb57a271babad8ccffbf733caa076 Patch
https://git.kernel.org/stable/c/d8e2973029b8b2ce477b564824431f3385c77083 Patch
Configurations

Configuration 1 (hide)

OR cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*
History

04 Apr 2025, 14:31

Type Values Removed Values Added
CPE cpe:2.3:o:linux:linux_kernel:5.13:rc2:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc1:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc5:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc6:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc3:*:*:*:*:*:*
cpe:2.3:o:linux:linux_kernel:5.13:rc4:*:*:*:*:*:*
First Time Linux linux Kernel
Linux
References () https://git.kernel.org/stable/c/0dc13e75507faa17ac9f7562b4ef7bf8fcd78422 - () https://git.kernel.org/stable/c/0dc13e75507faa17ac9f7562b4ef7bf8fcd78422 - Patch
References () https://git.kernel.org/stable/c/1e28018b5c83d5073f74a6fb72eabe8370b2f501 - () https://git.kernel.org/stable/c/1e28018b5c83d5073f74a6fb72eabe8370b2f501 - Patch
References () https://git.kernel.org/stable/c/3dd2aeac2e9624cff9fa634710837e4f2e352758 - () https://git.kernel.org/stable/c/3dd2aeac2e9624cff9fa634710837e4f2e352758 - Patch
References () https://git.kernel.org/stable/c/6cff57eea3347f79f1867cc53e1093b6614138d8 - () https://git.kernel.org/stable/c/6cff57eea3347f79f1867cc53e1093b6614138d8 - Patch
References () https://git.kernel.org/stable/c/77de6ee73f54a9a89c0afa0bf4c53b239aa9953a - () https://git.kernel.org/stable/c/77de6ee73f54a9a89c0afa0bf4c53b239aa9953a - Patch
References () https://git.kernel.org/stable/c/ac31cc837cafb57a271babad8ccffbf733caa076 - () https://git.kernel.org/stable/c/ac31cc837cafb57a271babad8ccffbf733caa076 - Patch
References () https://git.kernel.org/stable/c/d8e2973029b8b2ce477b564824431f3385c77083 - () https://git.kernel.org/stable/c/d8e2973029b8b2ce477b564824431f3385c77083 - Patch

21 Nov 2024, 06:35

Type Values Removed Values Added
References () https://git.kernel.org/stable/c/0dc13e75507faa17ac9f7562b4ef7bf8fcd78422 - () https://git.kernel.org/stable/c/0dc13e75507faa17ac9f7562b4ef7bf8fcd78422 -
References () https://git.kernel.org/stable/c/1e28018b5c83d5073f74a6fb72eabe8370b2f501 - () https://git.kernel.org/stable/c/1e28018b5c83d5073f74a6fb72eabe8370b2f501 -
References () https://git.kernel.org/stable/c/3dd2aeac2e9624cff9fa634710837e4f2e352758 - () https://git.kernel.org/stable/c/3dd2aeac2e9624cff9fa634710837e4f2e352758 -
References () https://git.kernel.org/stable/c/6cff57eea3347f79f1867cc53e1093b6614138d8 - () https://git.kernel.org/stable/c/6cff57eea3347f79f1867cc53e1093b6614138d8 -
References () https://git.kernel.org/stable/c/77de6ee73f54a9a89c0afa0bf4c53b239aa9953a - () https://git.kernel.org/stable/c/77de6ee73f54a9a89c0afa0bf4c53b239aa9953a -
References () https://git.kernel.org/stable/c/ac31cc837cafb57a271babad8ccffbf733caa076 - () https://git.kernel.org/stable/c/ac31cc837cafb57a271babad8ccffbf733caa076 -
References () https://git.kernel.org/stable/c/d8e2973029b8b2ce477b564824431f3385c77083 - () https://git.kernel.org/stable/c/d8e2973029b8b2ce477b564824431f3385c77083 -

03 Jul 2024, 01:37

Type Values Removed Values Added
Summary
  • (es) En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: net: ipv4: corrige la pérdida de memoria en ip_mc_add1_src. BUG: pérdida de memoria objeto sin referencia 0xffff888101bc4c00 (tamaño 32): comm "syz-executor527", pid 360, jiffies 4294807421 (edad 19.329s) volcado hexadecimal (primeros 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 01 00 00 00 00 00 00 00 ac 14 14 bb 00 00 02 00 ................ backtrace: [&lt;00000000f17c5244&gt;] kmalloc include/linux/slab.h:558 [en línea] [&lt;00000000f17c5244&gt;] kzalloc include/ linux/slab.h:688 [en línea] [&lt;00000000f17c5244&gt;] ip_mc_add1_src net/ipv4/igmp.c:1971 [en línea] [&lt;00000000f17c5244&gt;] ip_mc_add_src+0x95f/0xdb0 net/ipv4/igmp.c:2095 &lt;000000001cb99709 &gt;] ip_mc_source+0x84c/0xea0 net/ipv4/igmp.c:2416 [&lt;0000000052cf19ed&gt;] do_ip_setsockopt net/ipv4/ip_sockglue.c:1294 [en línea] [&lt;0000000052cf19ed&gt;] 0net/ipv4/ip_sockglue. c:1423 [&lt;00000000477edfbc&gt;] raw_setsockopt+0x13d/0x170 net/ipv4/raw.c:857 [&lt;00000000e75ca9bb&gt;] __sys_setsockopt+0x158/0x270 net/socket.c:2117 [&lt;00000000bdb993 a8&gt;] __do_sys_setsockopt net/socket.c :2128 [en línea] [&lt;00000000bdb993a8&gt;] __se_sys_setsockopt net/socket.c:2125 [en línea] [&lt;00000000bdb993a8&gt;] __x64_sys_setsockopt+0xba/0x150 net/socket.c:2125 [&lt;000000006a 1ffdbd&gt;] do_syscall_64+0x40/0x80 arch/ x86/entry/common.c:47 [&lt;00000000b11467c4&gt;] Entry_SYSCALL_64_after_hwframe+0x44/0xae En la confirmación 24803f38a5c0 ("igmp: no eliminar la información de la lista de fuentes de igmp cuando se establece el enlace"), se eliminó ip_mc_clear_src() en ip_mc_destroy_dev() , porque también fue llamado en igmpv3_clear_delrec(). Gráfico de llamada aproximado: inetdev_destroy -&gt; ip_mc_destroy_dev -&gt; igmpv3_clear_delrec -&gt; ip_mc_clear_src -&gt; RCU_INIT_POINTER(dev-&gt;ip_ptr, NULL) Sin embargo, ip_mc_clear_src() llamado en igmpv3_clear_delrec() no libera in_dev-&gt;mc_list-&gt;sources. Y RCU_INIT_POINTER() asigna NULL a dev-&gt;ip_ptr. Como resultado, in_dev no se puede obtener a través de inetdev_by_index() y luego in_dev-&gt;mc_list-&gt;sources no se puede liberar mediante ip_mc_del1_src() en sock_close. La secuencia de llamada aproximada es así: sock_close -&gt; __sock_release -&gt; inet_release -&gt; ip_mc_drop_socket -&gt; inetdev_by_index -&gt; ip_mc_leave_src -&gt; ip_mc_del_src -&gt; ip_mc_del1_src Entonces todavía necesitamos llamar a ip_mc_clear_src() en ip_mc_destroy_dev() para liberar in_dev-&gt;mc_list -&gt;fuentes .
CWE CWE-400
CVSS v2 : unknown
v3 : unknown 		v2 : unknown
v3 : 5.5

21 May 2024, 15:15

Type Values Removed Values Added
New CVE
Information

Published : 2024-05-21 15:15

Updated : 2025-04-04 14:31

NVD link : CVE-2021-47238

Mitre link : CVE-2021-47238

CVE.ORG link : CVE-2021-47238

JSON object : View

Products Affected

linux

CWE
CWE-400

Uncontrolled Resource Consumption