Vulnerability in Kernel (CVE-2025-71087)

Summary

Vulnerability in Kernel (CVE-2025-71087). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.4 or later.

Original description

The description as published by the source.

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

iavf: fix off-by-one issues in iavf_config_rss_reg()

There are off-by-one bugs when configuring RSS hash key and lookup
table, causing out-of-bounds reads to memory [1] and out-of-bounds
writes to device registers.

Before commit 43a3d9ba34c9 ("i40evf: Allow PF driver to configure RSS"),
the loop upper bounds were:
i <= I40E_VFQF_{HKEY,HLUT}_MAX_INDEX
which is safe since the value is the last valid index.

That commit changed the bounds to:
i <= adapter->rss_{key,lut}_size / 4
where rss_{key,lut}_size / 4 is the number of dwords, so the last
valid index is (rss_{key,lut}_size / 4) - 1. Therefore, using <=
accesses one element past the end.

Fix the issues by using < instead of <=, ensuring we do not exceed
the bounds.

[1] KASAN splat about rss_key_size off-by-one
BUG: KASAN: slab-out-of-bounds in iavf_config_rss+0x619/0x800
Read of size 4 at addr ffff888102c50134 by task kworker/u8:6/63

CPU: 0 UID: 0 PID: 63 Comm: kworker/u8:6 Not tainted 6.18.0-rc2-enjuk-tnguy-00378-g3005f5b77652-dirty #156 PREEMPT(voluntary)
Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2 04/01/2014
Workqueue: iavf iavf_watchdog_task
Call Trace:

dump_stack_lvl+0x6f/0xb0
print_report+0x170/0x4f3
kasan_report+0xe1/0x1a0
iavf_config_rss+0x619/0x800
iavf_watchdog_task+0x2be7/0x3230
process_one_work+0x7fd/0x1420
worker_thread+0x4d1/0xd40
kthread+0x344/0…

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

Auto-generated summary

Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.

A vulnerability tracked as CVE-2025-71087 has been found in Kernel.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Kernel to 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.4 or later.
If unsure, ask your IT team or search "Kernel CVE-2025-71087" on the vendor's site.

CVE-2025-71087 (Kernel)
Patched: 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.4 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.

❓ What is the problem

A vulnerability (unclassified) exists in Kernel.

📍 Affected scope

Check the vendor advisory for the affected versions of Kernel.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.4.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Kernel' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.

Response actions

Concrete steps and command examples for SOC/SRE teams to execute in order

1
Identify exposure identify
```
grep -r 'Kernel' . | grep -v node_modules
```
リポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で Kernel を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Kernel to 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.4
```
ステージング環境で 5.10.248, 5.15.198, 6.1.160, 6.6.120, 6.12.64, 6.18.4 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
3
Post-deployment verification verify
```
Confirm patched version is live in production
```
パッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。

Affected packages

Linux Kernel

[{"type":"ECOSYSTEM","events":[{"introduced":"4.7.0"},{"fixed":"5.10.248"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.11.0"},{"fixed":"5.15.198"}]},{"type":"ECOSYSTEM","events":[{"introduced":"5.16.0"},{"fixed":"6.1.160"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.2.0"},{"fixed":"6.6.120"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.7.0"},{"fixed":"6.12.64"}]},{"type":"ECOSYSTEM","events":[{"introduced":"6.13.0"},{"fixed":"6.18.4"}]}]

Fix status by distribution

Fixed packages published by each distribution for this CVE

BellSoft Alpaquita BELL-CVE-2025-71087 linux-lts Fixed in: 6.1.161-r0
Debian DEBIAN-CVE-2025-71087 linux Fixed in: 5.10.249-1
Ubuntu UBUNTU-CVE-2025-71087 linux-azure