high CVSS 7.1 EPSS <0.1%

CVE-2024-34777·Kernel vulnerability

In the Linux kernel, the following vulnerability has been resolved: dma-mapping: benchmark: fix node id validation While validating node ids in map_benchmark_ioctl(), node_possible() may be provided with invalid argument outside of [0,MAX_NUMNODES-1] range leading to: BUG: KASAN: wild-memory-access in map_benchmark_ioctl (kernel/dma/map_benchmark.c:214) Read of size 8 at addr 1fffffff8ccb6398 by task dma_map_benchma/971 CPU: 7 PID: 971 Comm: dma_map_benchma Not tainted 6.9.0-rc6 #37 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) Call Trace: <TASK> dump_stack_lvl (lib/dump_stack.c:117) kasan_report (mm/kasan/report.c:603) kasan_check_range (mm/kasan/generic.c:189) variable_test_bit (arch/x86/include/asm/bitops.h:227) [inline] arch_test_bit (arch/x86/include/asm/bitops.h:239) [inline] _test_bit at (include/asm-generic/bitops/instrumented-non-atomic.h:142) [inline] node_state (include/linux/nodemask.h:423) [inline] map_benchmark_ioctl (kernel/dma/map_benchmark.c:214) full_proxy_unlocked_ioctl (fs/debugfs/file.c:333) __x64_sys_ioctl (fs/ioctl.c:890) do_syscall_64 (arch/x86/entry/common.c:83) entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:130) Compare node ids with sane bounds first. NUMA_NO_NODE is considered a special valid case meaning that benchmarking kthreads won't be bound to a cpuset of a given node. Found by Linux Verification Center (linuxtesting.org).

Severity
high
Software
Kernel
Fixed in
6.9.4
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% — higher than 14% 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-2024-34777 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: 6.9.4

Fixed in: 6.9.4

How to fix this CVE

Update your Linux kernel to version 6.9.4 or later to patch this memory validation flaw in the DMA mapping benchmark module. The vulnerability allows out-of-bounds node ID validation that can trigger memory access errors; applying the kernel update eliminates this input validation gap.

sudo dnf upgrade 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 compare against 6.9.4—versions 6.7 through 6.9.3 are vulnerable
  2. Step 2: Verify if the DMA benchmark module is loaded via `lsmod | grep dma_map_benchmark` or check `/sys/kernel/debug/dma_map_benchmark` exists
  3. Step 3: Search kernel logs for KASAN wild-memory-access errors using `journalctl -k | grep -i 'wild-memory-access\|map_benchmark'` or `dmesg | grep -i 'kasan.*map_benchmark'`
  4. Step 4: After updating, confirm the patch with `uname -r` showing kernel ≥6.9.4, then retest with `cat /sys/kernel/debug/dma_map_benchmark` to ensure no KASAN errors occur

FAQ

What is CVE-2024-34777?

CVE-2024-34777 is a kernel vulnerability in the DMA mapping benchmark module where node ID validation fails to check bounds before calling node_possible(), causing out-of-bounds memory reads and potential system crashes via KASAN detection.

Is CVE-2024-34777 being actively exploited?

No—CISA does not list CVE-2024-34777 in the Known Exploited Vulnerabilities catalog, and no public exploits are available. Exploitation requires local kernel module access.

What versions of Kernel are affected by CVE-2024-34777?

Linux kernel versions 6.7 through 6.9.3 are vulnerable. Version 6.9.4 and later contain the fix.

How do I check if my server is vulnerable to CVE-2024-34777?

Run `uname -r` to display your kernel version—if it is 6.7.x, 6.8.x, or 6.9.0-6.9.3, your system is vulnerable and requires an immediate kernel update.

Does Defensia detect CVE-2024-34777?

Yes — Defensia's CVE advisory scanner compares installed package versions against the NVD database. If Kernel is installed on a monitored server, CVE-2024-34777 will appear in your dashboard with remediation steps.

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References

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