Buffer overflow in Linux
CVE-2025-38538
In the Linux kernel, the following vulnerability has been resolved: dmaengine: nbpfaxi: Fix memory corruption in probe() The nbpf->chan[] array is allocated earlier in the nbpf_probe() function and it has "num_channels" elements. These three loops iterate one element farther than they should and corrupt memory. The changes to the second loop are more involved. In this case, we're copying data from the irqbuf[] array into the nbpf->chan[] array. If the data in irqbuf[i] is the error IRQ then we skip it, so the iterators are not in sync. I added a check to ensure that we don't go beyond the end of the irqbuf[] array. I'm pretty sure this can't happen, but it seemed harmless to add a check. On the other hand, after the loop has ended there is a check to ensure that the "chan" iterator is where we expect it to be. In the original code we went one element beyond the end of the array so the iterator wasn't in the correct place and it would always return -EINVAL. However, now it will always be in the correct place. I deleted the check since we know the result.
Vulnerability class: Buffer Overflow
EPSS: 0.002 (6.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
Affected products
- Linux — versions b45b262cefd5b8eb2ba88d20e5bd295881293894, 3.17, 0
- Linux Linux_kernel — versions 6.16
- Debian Debian_linux — versions 11.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67 (Patch)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
- af854a3a-2127-422b-91ae-364da2661108 (Mailing List, Third Party Advisory)
Frequently asked questions
- What is CVE-2025-38538?
- CVE-2025-38538 is a high-severity vulnerability in Linux, classified under Out-of-bounds Write. CVSS score: 7.8/10. Published 2025-08-16.
- How severe is CVE-2025-38538?
- High severity. CVSS v3 base score is 7.8 out of 10.
- Is CVE-2025-38538 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.