high CVSS 7.1 EPSS <0.1%

CVE-2024-53099·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: bpf: Check validity of link->type in bpf_link_show_fdinfo() If a newly-added link type doesn't invoke BPF_LINK_TYPE(), accessing bpf_link_type_strs[link->type] may result in an out-of-bounds access. To spot such missed invocations early in the future, checking the validity of link->type in bpf_link_show_fdinfo() and emitting a warning when such invocations are missed.

Severity
high
Software
Kernel
Fixed in
6.11.9
Published

How likely is exploitation

FIRST's Exploit Prediction Scoring System puts the probability of this CVE being exploited in the next 30 days at <0.1% — in the bottom 1% of all published CVEs. EPSS is an independent forecast of exploitation, not a severity rating: it says nothing about how much damage a successful attack does, which is what a CVSS score measures.

Read the two together. CVE-2024-53099 scores 7.1 on CVSS, so a successful attack would be serious — but at <0.1%, almost nobody is currently attempting it. That is a different situation from a flaw under mass exploitation, and it is usually the difference between patching on your next maintenance window and patching tonight.

Affected versions

From: 6.7

Until: 6.11.9

Fixed in: 6.11.9

How to fix this CVE

Update your Linux kernel to version 6.11.9 or later to patch an out-of-bounds memory access vulnerability in the BPF subsystem. This flaw occurs when newly-added BPF link types fail to register themselves properly, potentially causing kernel information disclosure or denial of service. Apply the patch immediately, especially if your systems run kernel versions 6.7 through 6.11.8.

sudo dnf update kernel kernel-devel

Defensia detects this vulnerability

How to check if you are affected

  1. Step 1: Check your current kernel version with `uname -r` and verify if it falls within the vulnerable range (6.7 to 6.11.8)
  2. Step 2: Inspect loaded BPF programs using `bpftool prog list` to identify if custom or third-party BPF link types are in use on the system
  3. Step 3: Search kernel logs for BPF-related warnings with `dmesg | grep -i bpf` or `journalctl -u kernel | grep -i bpf` to detect any link type validation errors
  4. Step 4: After patching, reboot the system with `sudo reboot` and confirm the new kernel version with `uname -r` to ensure version 6.11.9 or later is running

FAQ

What is CVE-2024-53099?

This vulnerability is a memory bounds checking flaw in the Linux kernel's BPF (Berkeley Packet Filter) subsystem where unregistered BPF link types can trigger out-of-bounds array access, potentially leaking kernel memory or causing a crash.

Is CVE-2024-53099 being actively exploited?

No, this vulnerability is not listed on the CISA Known Exploited Vulnerabilities (KEV) catalog and has no publicly available exploits at this time.

What versions of Kernel are affected by CVE-2024-53099?

Linux kernel versions 6.7 through 6.11.8 are vulnerable; kernel 6.11.9 and later versions contain the fix.

How do I check if my server is vulnerable to CVE-2024-53099?

Run `uname -r` to display your kernel version and compare it against the vulnerable range; if your version is between 6.7 and 6.11.8 (inclusive), your system is affected.

Does Defensia detect CVE-2024-53099?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2024-53099 will appear in your dashboard with remediation steps.

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References

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