CVE-2025-40206
- Source
- https://cve.org/CVERecord?id=CVE-2025-40206
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-40206.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2025-40206
- Downstream
- Related
- Published
- 2025-11-12T21:56:35Z
- Modified
- 2026-08-25T03:30:12Z
- Severity
-
- 7.8 (High) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H CVSS Calculator
- Summary
- netfilter: nft_objref: validate objref and objrefmap expressions
- Details
-
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nft_objref: validate objref and objrefmap expressions
Referencing a synproxy stateful object from OUTPUT hook causes kernel crash due to infinite recursive calls:
BUG: TASK stack guard page was hit at 000000008bda5b8c (stack is 000000003ab1c4a5..00000000494d8b12) [...] Call Trace: __find_rr_leaf+0x99/0x230 fib6_table_lookup+0x13b/0x2d0 ip6_pol_route+0xa4/0x400 fib6_rule_lookup+0x156/0x240 ip6_route_output_flags+0xc6/0x150 __nf_ip6_route+0x23/0x50 synproxy_send_tcp_ipv6+0x106/0x200 synproxy_send_client_synack_ipv6+0x1aa/0x1f0 nft_synproxy_do_eval+0x263/0x310 nft_do_chain+0x5a8/0x5f0 [nf_tables nft_do_chain_inet+0x98/0x110 nf_hook_slow+0x43/0xc0 __ip6_local_out+0xf0/0x170 ip6_local_out+0x17/0x70 synproxy_send_tcp_ipv6+0x1a2/0x200 synproxy_send_client_synack_ipv6+0x1aa/0x1f0 [...]
Implement objref and objrefmap expression validate functions.
Currently, only NFT_OBJECT_SYNPROXY object type requires validation. This will also handle a jump to a chain using a synproxy object from the OUTPUT hook.
Now when trying to reference a synproxy object in the OUTPUT hook, nft will produce the following error:
synproxy_crash.nft: Error: Could not process rule: Operation not supported synproxy name mysynproxy ^^^^^^^^^^^^^^^^^^^^^^^^
- Database specific
{ "cna_assigner": "Linux", "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40206.json" }- References
-
- https://git.kernel.org/stable/c/0028e0134c64d9ed21728341a74fcfc59cd0f944
- https://git.kernel.org/stable/c/4c1cf72ec10be5a9ad264650cadffa1fbce6fabd
- https://git.kernel.org/stable/c/7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0
- https://git.kernel.org/stable/c/f31bcea12222a26d6f151df9c4a6d21f2eec1724
- https://git.kernel.org/stable/c/f359b809d54c6e3dd1d039b97e0b68390b0e53e4
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/40xxx/CVE-2025-40206.json
- https://nvd.nist.gov/vuln/detail/CVE-2025-40206
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected packages
Git / git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
Affected ranges
- Type
- GIT
- Repo
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- Events
-
Introducedee394f96ad7517fbc0de9106dcc7ce9efb14f264Fixedf31bcea12222a26d6f151df9c4a6d21f2eec1724Fixed0028e0134c64d9ed21728341a74fcfc59cd0f944Fixed7ea55a44493a5a36c3b3293b88bbe4841f9dbaf0Fixed4c1cf72ec10be5a9ad264650cadffa1fbce6fabdFixedf359b809d54c6e3dd1d039b97e0b68390b0e53e4