// For flags

CVE-2024-42109

netfilter: nf_tables: unconditionally flush pending work before notifier

Severity Score

5.5
*CVSS v3

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

Track
*SSVC
Descriptions

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unconditionally flush pending work before notifier syzbot reports: KASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831
KASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530
KASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597
Read of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45
[..]
Workqueue: events nf_tables_trans_destroy_work
Call Trace: nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline] nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline] nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Problem is that the notifier does a conditional flush, but its possible
that the table-to-be-removed is still referenced by transactions being
processed by the worker, so we need to flush unconditionally. We could make the flush_work depend on whether we found a table to delete
in nf-next to avoid the flush for most cases. AFAICS this problem is only exposed in nf-next, with
commit e169285f8c56 ("netfilter: nf_tables: do not store nft_ctx in transaction objects"),
with this commit applied there is an unconditional fetch of
table->family which is whats triggering the above splat.

In the Linux kernel, the following vulnerability has been resolved: netfilter: nf_tables: unconditionally flush pending work before notifier syzbot reports: KASAN: slab-uaf in nft_ctx_update include/net/netfilter/nf_tables.h:1831 KASAN: slab-uaf in nft_commit_release net/netfilter/nf_tables_api.c:9530 KASAN: slab-uaf int nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Read of size 2 at addr ffff88802b0051c4 by task kworker/1:1/45 [..] Workqueue: events nf_tables_trans_destroy_work Call Trace: nft_ctx_update include/net/netfilter/nf_tables.h:1831 [inline] nft_commit_release net/netfilter/nf_tables_api.c:9530 [inline] nf_tables_trans_destroy_work+0x152b/0x1750 net/netfilter/nf_tables_api.c:9597 Problem is that the notifier does a conditional flush, but its possible that the table-to-be-removed is still referenced by transactions being processed by the worker, so we need to flush unconditionally. We could make the flush_work depend on whether we found a table to delete in nf-next to avoid the flush for most cases. AFAICS this problem is only exposed in nf-next, with commit e169285f8c56 ("netfilter: nf_tables: do not store nft_ctx in transaction objects"), with this commit applied there is an unconditional fetch of table->family which is whats triggering the above splat.

Chenyuan Yang discovered that the CEC driver driver in the Linux kernel contained a use-after-free vulnerability. A local attacker could use this to cause a denial of service or possibly execute arbitrary code. Chenyuan Yang discovered that the USB Gadget subsystem in the Linux kernel did not properly check for the device to be enabled before writing. A local attacker could possibly use this to cause a denial of service.

*Credits: N/A
CVSS Scores
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High
Attack Vector
Local
Attack Complexity
Low
Authentication
Single
Confidentiality
None
Integrity
None
Availability
Complete
* Common Vulnerability Scoring System
SSVC
  • Decision:Track
Exploitation
None
Automatable
No
Tech. Impact
Partial
* Organization's Worst-case Scenario
Timeline
  • 2024-07-29 CVE Reserved
  • 2024-07-30 CVE Published
  • 2024-12-19 CVE Updated
  • 2025-04-15 EPSS 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"
>= 5.15.129 < 5.15.163
Search vendor "Linux" for product "Linux Kernel" and version " >= 5.15.129 < 5.15.163"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.1.50 < 6.1.98
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.1.50 < 6.1.98"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.5 < 6.6.39
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.5 < 6.6.39"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.5 < 6.9.9
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.5 < 6.9.9"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
>= 6.5 < 6.10
Search vendor "Linux" for product "Linux Kernel" and version " >= 6.5 < 6.10"
en
Affected
Linux
Search vendor "Linux"
Linux Kernel
Search vendor "Linux" for product "Linux Kernel"
6.4.13
Search vendor "Linux" for product "Linux Kernel" and version "6.4.13"
en
Affected