Linux KernelOperating system · Linux

CVE-2025-38320

HIGH · 7.1 CVSS v3.1 Published 2025-07-10

Fix available

A fix is available. Upgrade to 5.4.295 / 5.10.239 or later.

See remediation →

73/100

Remediation priority · Elevated

Zero-click Patch available

Official description

NVD · unedited

In the Linux kernel, the following vulnerability has been resolved: arm64/ptrace: Fix stack-out-of-bounds read in regs_get_kernel_stack_nth() KASAN reports a stack-out-of-bounds read in regs_get_kernel_stack_nth(). Call Trace: [ 97.283505] BUG: KASAN: stack-out-of-bounds in regs_get_kernel_stack_nth+0xa8/0xc8 [ 97.284677] Read of size 8 at addr ffff800089277c10 by task 1.sh/2550 [ 97.285732] [ 97.286067] CPU: 7 PID: 2550 Comm: 1.sh Not tainted 6.6.0+ #11 [ 97.287032] Hardware name: linux,dummy-virt (DT) [ 97.287815] Call trace: [ 97.288279] dump_backtrace+0xa0/0x128 [ 97.288946] show_stack+0x20/0x38 [ 97.289551] dump_stack_lvl+0x78/0xc8 [ 97.290203] print_address_description.constprop.0+0x84/0x3c8 [ 97.291159] print_report+0xb0/0x280 [ 97.291792] kasan_report+0x84/0xd0 [ 97.292421] __asan_load8+0x9c/0xc0 [ 97.293042] regs_get_kernel_stack_nth+0xa8/0xc8 [ 97.293835] process_fetch_insn+0x770/0xa30 [ 97.294562] kprobe_trace_func+0x254/0x3b0 [ 97.295271] kprobe_dispatcher+0x98/0xe0 [ 97.295955] kprobe_breakpoint_handler+0x1b0/0x210 [ 97.296774] call_break_hook+0xc4/0x100 [ 97.297451] brk_handler+0x24/0x78 [ 97.298073] do_debug_exception+0xac/0x178 [ 97.298785] el1_dbg+0x70/0x90 [ 97.299344] el1h_64_sync_handler+0xcc/0xe8 [ 97.300066] el1h_64_sync+0x78/0x80 [ 97.300699] kernel_clone+0x0/0x500 [ 97.301331] __arm64_sys_clone+0x70/0x90 [ 97.302084] invoke_syscall+0x68/0x198 [ 97.302746] el0_svc_common.constprop.0+0x11c/0x150 [ 97.303569] do_el0_svc+0x38/0x50 [ 97.304164] el0_svc+0x44/0x1d8 [ 97.304749] el0t_64_sync_handler+0x100/0x130 [ 97.305500] el0t_64_sync+0x188/0x190 [ 97.306151] [ 97.306475] The buggy address belongs to stack of task 1.sh/2550 [ 97.307461] and is located at offset 0 in frame: [ 97.308257] __se_sys_clone+0x0/0x138 [ 97.308910] [ 97.309241] This frame has 1 object: [ 97.309873] [48, 184) 'args' [ 97.309876] [ 97.310749] The buggy address belongs to the virtual mapping at [ 97.310749] [ffff800089270000, ffff800089279000) created by: [ 97.310749] dup_task_struct+0xc0/0x2e8 [ 97.313347] [ 97.313674] The buggy address belongs to the physical page: [ 97.314604] page: refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x14f69a [ 97.315885] flags: 0x15ffffe00000000(node=1|zone=2|lastcpupid=0xfffff) [ 97.316957] raw: 015ffffe00000000 0000000000000000 dead000000000122 0000000000000000 [ 97.318207] raw: 0000000000000000 0000000000000000 00000001ffffffff 0000000000000000 [ 97.319445] page dumped because: kasan: bad access detected [ 97.320371] [ 97.320694] Memory state around the buggy address: [ 97.321511] ffff800089277b00: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 97.322681] ffff800089277b80: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 [ 97.323846] >ffff800089277c00: 00 00 f1 f1 f1 f1 f1 f1 00 00 00 00 00 00 00 00 [ 97.325023] ^ [ 97.325683] ffff800089277c80: 00 00 00 00 00 00 00 00 00 f3 f3 f3 f3 f3 f3 f3 [ 97.326856] ffff800089277d00: f3 f3 00 00 00 00 00 00 00 00 00 00 00 00 00 00 This issue seems to be related to the behavior of some gcc compilers and was also fixed on the s390 architecture before: commit d93a855c31b7 ("s390/ptrace: Avoid KASAN false positives in regs_get_kernel_stack_nth()") As described in that commit, regs_get_kernel_stack_nth() has confirmed that `addr` is on the stack, so reading the value at `*addr` should be allowed. Use READ_ONCE_NOCHECK() helper to silence the KASAN check for this case. [will: Use '*addr' as the argument to READ_ONCE_NOCHECK()]

Technical summary

dbcve analysis

How this class of weakness works · CWE-125

The code reads past the end (or before the start) of a buffer, returning memory that was never meant to be exposed. Attackers use it to leak secrets like keys or to defeat memory-protection defences. Remediation is validating indices and lengths before every read.

General guidance for the out-of-bounds read class — the official description and references above are authoritative for this specific CVE. Want a bespoke review and a reviewed fix? Ask our team →

Affected products & versions

NVD · CPE data

Linux KernelOperating system

Affected:>= 4.8, < 5.4.295>= 5.5, < 5.10.239>= 5.11, < 5.15.186>= 5.16, < 6.1.142>= 6.2, < 6.6.95>= 6.7, < 6.12.35>= 6.13, < 6.15.4= 6.16

Debian LinuxOperating system

Affected:= 11.0

CVSS breakdown

From the vector

Attack vector: Local
Complexity: Low
Privileges: Low
User interaction: None
Scope: Unchanged
Confidentiality: High
Integrity: None
Availability: High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:H

Remediation

dbcve · scoped

Upgrade available Upgrade to 5.4.295 / 5.10.239 / 5.15.186 or later

Fixed in 5.4.2955.10.2395.15.186

Vendor patch git.kernel.org →

Recommended fix High confidence

Linux Kernel 5.4.295, 5.10.239, 5.15.186, or 6.1.142 (or later stable releases); Debian 11.0 kernel update from Debian security repositories

1. Identify the currently running kernel version using 'uname -r' or 'cat /proc/version'
2. For RHEL/CentOS systems: Update kernel via 'yum update' or 'dnf update' and reboot to the new kernel version
3. For Ubuntu/Debian systems: Run 'apt-get update && apt-get upgrade' to install the latest kernel packages, then reboot
4. For Amazon Linux: Run 'amazon-linux-extras update' and 'yum update kernel', then reboot
5. Verify the fix is applied by checking the kernel version after reboot matches or exceeds the fixed versions: 5.4.295, 5.10.239, 5.15.186, or 6.1.142 depending on your base release
6. Confirm the vulnerability is resolved by verifying 'regs_get_kernel_stack_nth' no longer triggers KASAN warnings or by checking for the presence of the READ_ONCE_NOCHECK fix in the kernel source

Caveat Kernel upgrades may require system downtime for reboot; ensure compatibility with custom kernel modules or proprietary drivers before upgrading

Generated from the published advisory — verify against the referenced sources before acting.

We can perform the upgrade in your staging environment and verify nothing breaks — typical engagement from $3,200. Get the upgrade done

Scan for this in your stack

Free · runs locally

dbcve dependency scanner

Check whether your project pulls in CVE-2025-38320 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References

Primary sources

git.kernel.orgPatch / commit
git.kernel.orgPatch
git.kernel.orgPatch
git.kernel.orgPatch
git.kernel.orgPatch
git.kernel.orgPatch
git.kernel.orgPatch
git.kernel.orgPatch
git.kernel.orgPatch
lists.debian.orgThird Party Advisory
lists.debian.orgThird Party Advisory
nvd.nist.govNVD record

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2025-38320 in production — separate from our analysis above.

Notes0 Guidelines

Know something about CVE-2025-38320?

The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.

The version that genuinely resolved it — not the one the vendor claimed
A config change or rule that shut the vector down
A gotcha in the upgrade path that cost you an afternoon

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here

Verified mitigations, workarounds, and config changes
Version or environment caveats, and links to real fixes
No weaponised exploit code, or anything meant to cause harm
No spam, self-promotion, credentials, or personal data

At a glance

A fix existsUpgrade to 5.4.295 / 5.10.239 or later

Severity 7.1 High

Exploit likelihood EPSS, next 30 days 0.2%

Affects: Linux Kernel

Remediation

Need this fixed?

Get a fix

Estimated effortfrom ~18 hrs

ComplexityComplex

Typical engagementfrom $3,200

What a fix involves

We scope it with you and confirm a fixed quote
A specialist builds a reviewed fix
You deploy it to staging first
Optional re-test once it’s live

We specialise in CVE remediation. Send your environment and we’ll scope CVE-2025-38320 and return a fixed quote.

You’ll deal with our team directly and deploy the reviewed fix to staging first — never straight to production.

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

Scan for this in your stack

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Practitioner notes

No notes yet

Official description

Technical summary

Affected products & versions

CVSS breakdown

Remediation

References