Vulnerability in Linux kernel (CVE-2026-97965)
Summary
Vulnerability in Linux kernel (CVE-2026-97965). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
vxlan: initialize _md in vxlan_xmit_one()
If a VXLAN device is configured with both VXLAN_F_COLLECT_METADATA and
VXLAN_F_GBP, and a packet is transmitted through it using an external
ip_tunnel_info that lacks the IP_TUNNEL_VXLAN_OPT_BIT flag, md is left
pointing to the uninitialized _md stack variable:
if (test_bit(IP_TUNNEL_VXLAN_OPT_BIT, info->key.tun_flags)) {
if (info->options_len < sizeof(*md))
goto drop;
md = ip_tunnel_info_opts(info);
}
Because IP_TUNNEL_VXLAN_OPT_BIT is not set, md is not updated and remains
pointing to _md. Later, vxlan_build_skb() is called with md, which
eventually calls vxlan_build_gbp_hdr():
if (vxflags & VXLAN_F_GBP)
vxlan_build_gbp_hdr(vxh, md);
Inside vxlan_build_gbp_hdr(), md->gbp is read:
if (!md->gbp)
return;
gbp = (struct vxlanhdr_gbp *)vxh;
...
if (md->gbp & VXLAN_GBP_DONT_LEARN)
gbp->dont_learn = 1;
If the stack contains garbage, this causes:
- VXLAN_HF_GBP flag to be spuriously set in the VXLAN header.
- gbp->dont_learn and gbp->policy_applied to be set from stack bits.
- gbp->policy_id to receive 16 bits of uninitialized kernel stack data,
leaking it onto the wire.
Fix this by zero-initializing _md. If IP_TUNNEL_VXLAN_OPT_BIT is not
present, md->gbp remains…
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-2026-97965 has been found in Linux kernel.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-97965" on the vendor's site.
CVE-2026-97965 (Linux kernel)
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.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: ?. Risk of unauthorized operations or information disclosure.
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。
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com