CVE-2026-97965vxlan: initialize _md in vxlan_xmit_one()
- —Not scoredno CVSS score yet
- 0.17%Exploitation in 30 daysEPSS · top 94% of all CVEs
- NoKnown exploitednot in CISA's KEV catalog
- NonePublic exploitsnone known yet
Description
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: 1) VXLAN_HF_GBP flag to be spuriously set in the VXLAN header. 2) gbp->dont_learn and gbp->policy_applied to be set from stack bits. 3) 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 0, and vxlan_build_gbp_hdr() returns early without modifying the VXLAN header.
Timeline
ID reserved
By Linux
Published
- 26 days later
· 26 days later
Record updated
Changes after publication (a new score, a public exploit, EPSS crossing 1, 10 or 50 %, leaving KEV) are kept since November 2026; earlier ones are not known.
Scores
No CVSS score yet: neither the CNA, CISA nor NVD has scored this CVE. NVD status: Received.
- EPSS (exploitation in 30 days)
- 0.17% · top 94% of all CVEs (14 Nov 2026)
The list uses the assigner's score when there is one, then CISA's, then NVD's: Not scored.
Affected products
- affected ee122c79d4227f6ec642157834b6a90fcffa4382 – < fb78beb64e0e79557e4cd7cd17fea744bb6f01d9
- affected ee122c79d4227f6ec642157834b6a90fcffa4382 – < 0d13b5a413bffc8718b3821b78537ccc6596c233
- affected ee122c79d4227f6ec642157834b6a90fcffa4382 – < bfb74c48ac2d31476d5e09cf9658844508d2608a
- affected ee122c79d4227f6ec642157834b6a90fcffa4382 – < 081f22177d9d12b1e381b787f203cd5f47508187
- affected ee122c79d4227f6ec642157834b6a90fcffa4382 – < be83178bfc44588f6e3adb827ed874c683193466
- affected 4.3
- unaffected < 4.3
- unaffected 6.6.160 – ≤ 6.6.*
- unaffected 6.12.111 – ≤ 6.12.*
- unaffected 6.18.53 – ≤ 6.18.*
- unaffected 7.2.7 – ≤ 7.2.*
- unaffected 7.3 – ≤ *
References
References5
- https://git.kernel.org/stable/c/fb78beb64e0e79557e4cd7cd17fea744bb6f01d9 (opens in a new tab)
- https://git.kernel.org/stable/c/0d13b5a413bffc8718b3821b78537ccc6596c233 (opens in a new tab)
- https://git.kernel.org/stable/c/bfb74c48ac2d31476d5e09cf9658844508d2608a (opens in a new tab)
- https://git.kernel.org/stable/c/081f22177d9d12b1e381b787f203cd5f47508187 (opens in a new tab)
- https://git.kernel.org/stable/c/be83178bfc44588f6e3adb827ed874c683193466 (opens in a new tab)
Sources
The same CVE in the primary databases and aggregators, to check against.
- CVE.org record (opens in a new tab)
- CVE List JSON (GitHub) (opens in a new tab)
- NVD (opens in a new tab)
- FIRST EPSS (opens in a new tab)
- EUVD EUVD-2026-86819 (opens in a new tab)
- OSV.dev (opens in a new tab)
- GitHub Advisories (opens in a new tab)
- CIRCL Vulnerability-Lookup (opens in a new tab)
Badge for a README or a ticket
[](https://cveledger.app/cve/CVE-2026-97965)Record last updated .