CVE-2023-4206
published 2023-09-06CVE-2023-4206: A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation. When…
PriorityP342high7.8CVSS 3.1
AVLACLPRLUINSUCHIHAH
EPSS
0.56%
43.1th percentile
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation.
When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
Affected
16 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | debian_linux | — | — |
| debian | linux | < linux 6.1.52-1 (bookworm) | linux 6.1.52-1 (bookworm) |
| linux | kernel | >= 3.18 < 6.5 | 6.5 |
| linux | linux_kernel | >= 0 < 5.10.191-1 | 5.10.191-1 |
| linux | linux_kernel | >= 0 < 6.1.52-1 | 6.1.52-1 |
| linux | linux_kernel | >= 0 < 6.4.11-1 | 6.4.11-1 |
| linux | linux_kernel | >= 0 < 6.4.11-1 | 6.4.11-1 |
| linux | linux_kernel | >= 3.18 < 4.14.322 | 4.14.322 |
| linux | linux_kernel | >= 4.15 < 4.19.291 | 4.19.291 |
| linux | linux_kernel | >= 4.20 < 5.4.253 | 5.4.253 |
| linux | linux_kernel | >= 5.11 < 5.15.126 | 5.15.126 |
| linux | linux_kernel | >= 5.16 < 6.1.45 | 6.1.45 |
| linux | linux_kernel | >= 5.5 < 5.10.190 | 5.10.190 |
| linux | linux_kernel | >= 6.2 < 6.4.10 | 6.4.10 |
| msrc | cbl2_kernel_5.15.131.1-2_on_cbl_mariner_2.0 | — | — |
| paloalto | pan-os | — | — |
CVSS provenance
nvdv3.17.8HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
osv7.8HIGH
vendor_debian7.8HIGH
vendor_msrc7.8HIGH
vendor_redhat7.8HIGH
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OSV
CVE-2023-4206: A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation
osv·2023-09-06·CVSS 7.8
CVE-2023-4206 [HIGH] CVE-2023-4206: A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation. When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
GHSA
GHSA-r8pm-459q-x6hw: A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation
ghsa_unreviewed·2023-09-06
CVE-2023-4206 [HIGH] CWE-416 GHSA-r8pm-459q-x6hw: A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation.
When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
Palo Alto
PAN-SA-2024-0001 Informational Bulletin: Impact of OSS CVEs in PAN-OS
vendor_paloalto·2024-02-14·CVSS 9.8
CVE-2017-18342 [CRITICAL] PAN-SA-2024-0001 Informational Bulletin: Impact of OSS CVEs in PAN-OS
PAN-SA-2024-0001 Informational Bulletin: Impact of OSS CVEs in PAN-OS
The Palo Alto Networks Product Security Assurance team has evaluated the following open source software (OSS) CVEs as they relate to PAN-OS software. While PAN-OS software may include the
CVEs: CVE-2017-18342, CVE-2017-8923, CVE-2017-9120, CVE-2019-1551, CVE-2019-16865, CVE-2019-16905, CVE-2019-19523, CVE-2019-19528, CVE-2019-19911, CVE-2020-0404, CVE-2020-0431, CVE-2020-0466, CVE-2020-10379, CVE-2020-11538, CVE-2020-11608, CVE-2020-12114, CVE-2020-12321, CVE-2020-12362, CVE-2020-12363, CVE-2020-12364, CVE-2020-13757, CVE-2020-14314, CVE-2020-14351, CVE-2020-15778, CVE-2020-1967, CVE-2020-24394, CVE-2020-24504, CVE-2020-25211, CVE-2020-25212, CVE-2020-25284, CVE-2020-25285, CVE-2020-25717, CVE-2020-26541, CVE-2020-2715
Microsoft
Use-after-free in Linux kernel's net/sched: cls_route component
vendor_msrc·2023-09-12·CVSS 7.8
CVE-2023-4206 [HIGH] CWE-416 Use-after-free in Linux kernel's net/sched: cls_route component
Use-after-free in Linux kernel's net/sched: cls_route component
FAQ: Is Azure Linux the only Microsoft product that includes this open-source library and is therefore potentially affected by this vulnerability?
One of the main benefits to our customers who choose to use the Azure Linux distro is the commitment to keep it up to date with the most recent and most secure versions of the open source libraries with which the distro is composed. Microsoft is committed to transparency in this work which is why we began publishing CSAF/VEX in October 2025. See this blog post for more information. If impact to additional products is identified, we will update the CVE to reflect this.
Mariner: Mariner
Google: Google
Customer Action Required: Yes
Remediation: CBL-Mariner Releases
Reference: htt
Red Hat
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
vendor_redhat·2023-07-29·CVSS 7.8
CVE-2023-4206 [HIGH] CWE-416 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation.
When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
There are 3 CVEs for the use-after-free flaw found in net/sched/cls_fw.c in cla
Red Hat
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
vendor_redhat·2023-07-29·CVSS 7.8
CVE-2023-4207 [HIGH] CWE-416 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
A use-after-free vulnerability in the Linux kernel's net/sched: cls_fw component can be exploited to achieve local privilege escalation.
When fw_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit 76e42ae831991c828cffa8c37736ebfb831ad5ec.
There are 3 CVEs for the use-after-free flaw found in net/sched/cls_fw.c in classifier
Red Hat
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
vendor_redhat·2023-07-29·CVSS 7.8
CVE-2023-4208 [HIGH] CWE-416 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
A use-after-free vulnerability in the Linux kernel's net/sched: cls_u32 component can be exploited to achieve local privilege escalation.
When u32_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free.
We recommend upgrading past commit 3044b16e7c6fe5d24b1cdbcf1bd0a9d92d1ebd81.
There are 3 CVEs for the use-after-free flaw found in net/sched/cls_fw.c in classifi
Red Hat
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
vendor_redhat·2023-07-29·CVSS 7.8
CVE-2023-4128 [HIGH] CWE-416 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
This record is a duplicate of CVE-2023-4206, CVE-2023-4207, and CVE-2023-4208. Do not use this CVE record: CVE-2023-4128.
Statement: All CVE users should reference CVE-2023-4206, CVE-2023-4207, CVE-2023-4208 instead of this record. All references and descriptions in this record have been removed to prevent accidental usage.
Debian
CVE-2023-4206: linux - A use-after-free vulnerability in the Linux kernel's net/sched: cls_route compon...
vendor_debian·2023·CVSS 7.8
CVE-2023-4206 [HIGH] CVE-2023-4206: linux - A use-after-free vulnerability in the Linux kernel's net/sched: cls_route compon...
A use-after-free vulnerability in the Linux kernel's net/sched: cls_route component can be exploited to achieve local privilege escalation. When route4_change() is called on an existing filter, the whole tcf_result struct is always copied into the new instance of the filter. This causes a problem when updating a filter bound to a class, as tcf_unbind_filter() is always called on the old instance in the success path, decreasing filter_cnt of the still referenced class and allowing it to be deleted, leading to a use-after-free. We recommend upgrading past commit b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8.
Scope: local
bookworm: resolved (fixed in 6.1.52-1)
bullseye: resolved (fixed in 5.10.191-1)
forky: resolved (fixed in 6.4.11-1)
sid: resolved (fixed in 6.4.11-1)
trixie: resolved (fixed in 6
No detection rules found.
No public exploits indexed.
CTF
RIPTC / readme
ctf_writeups·CVSS 7.8
[HIGH] RIPTC / readme
`score:500` `solve_count:1`
"`Pwn`, `difficulty:Hard`
Lyrics: RIPTC
Composer: Krias aka Digging into kernel
I'm fond of the days that are retro
Hate the future's unpredictable echo
Peep into the kernel, take a look
Revive the code that the attack took
Found one new 0 day, what a magic
Triggering the moment, I've lost the knack
Patching up the class, secrets I pack
*Source code added a few files, ain't no pretense*
*Three characters added in another file, spotted only in vmlinux, no defense*
Friends from afar, they arrive
Could you help me thrive, like eating greens, time
`nc 47.88.23.76 7788`
[attachment](https://github.com/chaitin/Real-World-CTF-6th-Challenges/releases/download/x/riptc_attachment_241a4f7b8921b131e3237af987ad4f82.tar.gz)
Hint1 for RIPTC:
**Source code added a few
Bugzilla
CVE-2023-4206 CVE-2023-4207 CVE-2023-4208 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
bugzilla·2023-07-25·CVSS 7.8
CVE-2023-4206 [HIGH] CVE-2023-4206 CVE-2023-4207 CVE-2023-4208 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
CVE-2023-4206 CVE-2023-4207 CVE-2023-4208 kernel: net/sched: Use-after-free vulnerabilities in the net/sched classifiers: cls_fw, cls_u32 and cls_route
A flaw in the Linux Kernel found. Use after free in the net/sched classifiers (cls_fw, cls_u32 and cls_route) can happen because of mainline/net/sched/cls_fw.c incorrect handling of the existing filter in .change method that leads to an extra unbind_tcf call for the associated class and that allows that class to be removed while it's still used. These bugs can be used for a local privilege escalation.
Upstream patch:
https://lore.kernel.org/netdev/[email protected]/
Discussion:
*** Bug 2225499 has been marked as a duplicate of this bug. ***
---
Created kernel tracking bugs for this issue:
Affects: fedo
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8https://kernel.dance/b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlhttps://www.debian.org/security/2023/dsa-5492https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8https://kernel.dance/b80b829e9e2c1b3f7aae34855e04d8f6ecaf13c8https://lists.debian.org/debian-lts-announce/2024/01/msg00004.htmlhttps://www.debian.org/security/2023/dsa-5492
2023-09-06
Published