CVE-2026-53221
In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup() In vti6_tnl_lookup(), when an exact match for a tunnel fails, the code falls back to searching for wildcard tunnels: -…
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.58%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In the Linux kernel, the following vulnerability has been resolved: ip6_vti: fix incorrect tunnel matching in vti6_tnl_lookup() In vti6_tnl_lookup(), when an exact match for a tunnel fails, the code falls back to searching for wildcard tunnels: - Tunnels matching the packet's local address, with any remote address wildcard remote). - Tunnels matching the packet's remote address, with any local address (wildcard local). However, vti6 stores all these different types of tunnels in the same hash table (ip6n->tnls_r_l) prone to hash collisions. The bug is that the fallback search loops in vti6_tnl_lookup() were missing checks to ensure that the candidate tunnel actually has a wildcard address.
- CVSS 3.1
- 9.8 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- EPSS
- 0.58% probability · 47th percentile
- Public exploits
- None in Exploit-DB
- CISA KEV
- Not listed
- Weakness
- CWE-20
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
EPSS 0.6% since 26 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.
References
- https://git.kernel.org/stable/c/2abfb19bbb81958714ad1d43ebeb65b30394184bPatch
- https://git.kernel.org/stable/c/2fc7bc087cc7085368263d9d37bfe9a0bddd6a2dPatch
- https://git.kernel.org/stable/c/47fb3c2b4203556308e64354b3e78f2ce221d646Patch
- https://git.kernel.org/stable/c/90fd4513315ca07da99cfd8549d3e553a7160f0dPatch
- https://git.kernel.org/stable/c/a5c0359f5cbc51a2e2b114d6041e0f3c73f903e9Patch
- https://git.kernel.org/stable/c/c327fa4fca31415431202e063767a7ae342e19c6Patch
- https://git.kernel.org/stable/c/f513f308cc4bdb4530d033431592ffbc29b7fca1Patch
- https://git.kernel.org/stable/c/fc657ac0767c49839b3ef0b08dc0953ca30883f8Patch
- https://cert-portal.siemens.com/productcert/html/ssa-784472.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.