Out-of-Bounds Write in Linux kernel (CVE-2025-22056)
Summary
Out-of-bounds write in Linux kernel (CVE-2025-22056). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_tunnel: fix geneve_opt type confusion addition
When handling multiple NFTA_TUNNEL_KEY_OPTS_GENEVE attributes, the
parsing logic should place every geneve_opt structure one by one
compactly. Hence, when deciding the next geneve_opt position, the
pointer addition should be in units of char *.
However, the current implementation erroneously does type conversion
before the addition, which will lead to heap out-of-bounds write.
[ 6.989857] ==================================================================
[ 6.990293] BUG: KASAN: slab-out-of-bounds in nft_tunnel_obj_init+0x977/0xa70
[ 6.990725] Write of size 124 at addr ffff888005f18974 by task poc/178
[ 6.991162]
[ 6.991259] CPU: 0 PID: 178 Comm: poc-oob-write Not tainted 6.1.132 #1
[ 6.991655] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
[ 6.992281] Call Trace:
[ 6.992423]
[ 6.992586] dump_stack_lvl+0x44/0x5c
[ 6.992801] print_report+0x184/0x4be
[ 6.993790] kasan_report+0xc5/0x100
[ 6.994252] kasan_check_range+0xf3/0x1a0
[ 6.994486] memcpy+0x38/0x60
[ 6.994692] nft_tunnel_obj_init+0x977/0xa70
[ 6.995677] nft_obj_init+0x10c/0x1b0
[ 6.995891] nf_tables_newobj+0x585/0x950
[ 6.996922] nfnetlink_rcv_batch+0xdf9/0x1020
[ 6.998997] nfnetlink_rcv+0x1df/0x220
[ 6.999537] netlink_unicast+0x395/0x530
[ 7.000771]…
Source: NIST National Vulnerability Database NVD GitHub Advisory
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-2025-22056 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 7.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2025-22056" on the vendor's site.
CVE-2025-22056 (Linux kernel) — CWE-787 / CVSS v3 7.8
Attack vector: local / no user interaction
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.
Out-of-bounds write (CWE-787) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 7.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-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
Fix status by distribution
Fixed packages published by each distribution for this CVE
- BellSoft Alpaquita BELL-CVE-2025-22056 linux-lts Fixed in: 6.1.134-r0
- Debian DEBIAN-CVE-2025-22056 linux Fixed in: 5.10.237-1
- Ubuntu UBUNTU-CVE-2025-22056 linux-hwe-edge
References
- advisory nvd.nist.gov
- advisory github.com
- package git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web lists.debian.org
- web lists.debian.org
- web cert-portal.siemens.com
- web github.com
- web cert-portal.siemens.com