Linux Distros 未修補弱點:CVE-2021-47238

medium Nessus Plugin ID 224317

概要

Linux/Unix 主機上安裝的一個或多個套件存有弱點,供應商表示將不會修補。

說明

Linux/Unix 主機上安裝了一個或多個受到弱點影響的套件,且供應商未提供可用的修補程式。

- 在 Linux 核心中,已解決下列弱點: 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. (CVE-2021-47238)

請注意,Nessus 依賴供應商報告的套件存在。

解決方案

目前尚未有已知的解決方案。

Plugin 詳細資訊

嚴重性: Medium

ID: 224317

檔案名稱: unpatched_CVE_2021_47238.nasl

版本: 1.1

類型: local

代理程式: unix

系列: Misc.

已發布: 2025/3/5

已更新: 2025/3/5

支援的感應器: Nessus Agent, Nessus

風險資訊

VPR

風險因素: Medium

分數: 4.4

CVSS v2

風險因素: Medium

基本分數: 4.6

時間性分數: 3.4

媒介: CVSS2#AV:L/AC:L/Au:S/C:N/I:N/A:C

CVSS 評分資料來源: CVE-2021-47238

CVSS v3

風險因素: Medium

基本分數: 5.5

時間性分數: 4.8

媒介: CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

時間媒介: CVSS:3.0/E:U/RL:O/RC:C

弱點資訊

必要的 KB 項目: Host/local_checks_enabled, Host/cpu, global_settings/vendor_unpatched

可輕鬆利用: No known exploits are available

弱點發布日期: 2024/5/21

參考資訊

CVE: CVE-2021-47238