// For flags

CVE-2024-50257

netfilter: Fix use-after-free in get_info()

Severity Score

"-"
*CVSS v-

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved:

netfilter: Fix use-after-free in get_info()

ip6table_nat module unload has refcnt warning for UAF. call trace is:

WARNING: CPU: 1 PID: 379 at kernel/module/main.c:853 module_put+0x6f/0x80
Modules linked in: ip6table_nat(-)
CPU: 1 UID: 0 PID: 379 Comm: ip6tables Not tainted 6.12.0-rc4-00047-gc2ee9f594da8-dirty #205
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS rel-1.13.0-0-gf21b5a4aeb02-prebuilt.qemu.org 04/01/2014
RIP: 0010:module_put+0x6f/0x80
Call Trace:
<TASK>
get_info+0x128/0x180
do_ip6t_get_ctl+0x6a/0x430
nf_getsockopt+0x46/0x80
ipv6_getsockopt+0xb9/0x100
rawv6_getsockopt+0x42/0x190
do_sock_getsockopt+0xaa/0x180
__sys_getsockopt+0x70/0xc0
__x64_sys_getsockopt+0x20/0x30
do_syscall_64+0xa2/0x1a0
entry_SYSCALL_64_after_hwframe+0x77/0x7f

Concurrent execution of module unload and get_info() trigered the warning.
The root cause is as follows:

cpu0 cpu1
module_exit
//mod->state = MODULE_STATE_GOING
ip6table_nat_exit
xt_unregister_template
kfree(t)
//removed from templ_list
getinfo()
t = xt_find_table_lock
list_for_each_entry(tmpl, &xt_templates[af]...)
if (strcmp(tmpl->name, name))
continue; //table not found
try_module_get
list_for_each_entry(t, &xt_net->tables[af]...)
return t; //not get refcnt
module_put(t->me) //uaf
unregister_pernet_subsys
//remove table from xt_net list

While xt_table module was going away and has been removed from
xt_templates list, we couldnt get refcnt of xt_table->me. Check
module in xt_net->tables list re-traversal to fix it.

*Credits: N/A
CVSS Scores
Attack Vector
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Attack Complexity
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Privileges Required
-
User Interaction
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Scope
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Confidentiality
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Integrity
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Availability
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* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2024-10-21 CVE Reserved
  • 2024-11-09 CVE Published
  • 2024-11-15 EPSS Updated
  • 2024-11-19 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
CAPEC
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.15 < 5.15.171
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.15 < 5.15.171"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.15 < 6.1.116
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.15 < 6.1.116"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.15 < 6.6.60
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.15 < 6.6.60"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.15 < 6.11.7
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.15 < 6.11.7"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 5.15 < 6.12
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.15 < 6.12"
en
Affected