# CVE-2024-26586: mlxsw: spectrum_acl_tcam: Fix stack corruption

> A stack corruption vulnerability in the Linux kernel mlxsw driver allows local attackers to cause a system crash by adding specific network filters.

- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Local or same network only
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 22 Feb 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2024-26586, DEBIAN-CVE-2024-26586, GHSA-8pq4-pmqh-grvh, UBUNTU-CVE-2024-26586

## What is CVE-2024-26586?

CVE-2024-26586 is a high-severity memory corruption vulnerability in Linux kernel, published on 22 Feb 2024. It can only be exploited from the same machine or local network, with no action from the victim.

### Official description

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

mlxsw: spectrum_acl_tcam: Fix stack corruption

When tc filters are first added to a net device, the corresponding local
port gets bound to an ACL group in the device. The group contains a list
of ACLs. In turn, each ACL points to a different TCAM region where the
filters are stored. During forwarding, the ACLs are sequentially
evaluated until a match is found.

One reason to place filters in different regions is when they are added
with decreasing priorities and in an alternating order so that two
consecutive filters can never fit in the same region because of their
key usage.

In Spectrum-2 and newer ASICs the firmware started to report that the
maximum number of ACLs in a group is more than 16, but the layout of the
register that configures ACL groups (PAGT) was not updated to account
for that. It is therefore possible to hit stack corruption [1] in the
rare case where more than 16 ACLs in a group are required.

Fix by limiting the maximum ACL group size to the minimum between what
the firmware reports and the maximum ACLs that fit in the PAGT register.

Add a test case to make sure the machine does not crash when this
condition is hit.

[1]
Kernel panic - not syncing: stack-protector: Kernel stack is corrupted in: mlxsw_sp_acl_tcam_group_update+0x116/0x120
[...]
 dump_stack_lvl+0x36/0x50
 panic+0x305/0x330
 __stack_chk_fail+0x15/0x20
 mlxsw_sp_acl_tcam_group_update+0x116/0x120
 mlxsw_sp_acl_tcam_group_region_attach+0x69/0x110
 mlxsw_sp_acl_tcam_vchunk_get+0x492/0xa20
 mlxsw_sp_acl_tcam_ventry_add+0x25/0xe0
 mlxsw_sp_acl_rule_add+0x47/0x240
 mlxsw_sp_flower_replace+0x1a9/0x1d0
 tc_setup_cb_add+0xdc/0x1c0
 fl_hw_replace_filter+0x146/0x1f0
 fl_change+0xc17/0x1360
 tc_new_tfilter+0x472/0xb90
 rtnetlink_rcv_msg+0x313/0x3b0
 netlink_rcv_skb+0x58/0x100
 netlink_unicast+0x244/0x390
 netlink_sendmsg+0x1e4/0x440
 ____sys_sendmsg+0x164/0x260
 ___sys_sendmsg+0x9a/0xe0
 __sys_sendmsg+0x7a/0xc0
 do_syscall_64+0x40/0xe0
 entry_SYSCALL_64_after_hwframe+0x63/0x6b

Weakness: CWE-787 (Out-of-bounds Write)

## Which versions are affected by CVE-2024-26586?

It affects 1 product.


Products: Linux kernel.

## How do I fix CVE-2024-26586?

Apply the vendor's patch.

## Is CVE-2024-26586 being exploited?

There is no known exploitation of CVE-2024-26586 in the wild and no public exploit code.

## Other vulnerabilities in Linux kernel

- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2024-26586 and fix it if it is affected.

What it is: CVE-2024-26586 is a high-severity memory corruption vulnerability in Linux kernel, published on 22 Feb 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2024-26586 in the wild and no public exploit code.

Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2024-26586/ (Markdown: https://insights.sbomify.com/CVE-2024-26586/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2024-26586
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-26586
- OSV: https://osv.dev/vulnerability/CVE-2024-26586

---
From sbomify Insights: https://insights.sbomify.com/CVE-2024-26586/
Summaries are generated and may contain mistakes; the official description above is the record.