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EUVD-2026-344452

European Vulnerability Database identifier assigned by ENISA

Reserved

2026-10-02 07:56

Assigner

ENISA

Alias of

a CVE record, shown under related vulnerabilities. This identifier carries no description, severity or references of its own: they belong to that CVE.

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{
  "assigner": "ENISA",
  "date_reserved": "2026-10-02T07:56:14.753110+00:00",
  "id": "EUVD-2026-344452"
}

CVE-2021-47309 (GCVE-0-2021-47309)

Vulnerability from cvelistv5 – Published: 2024-05-21 14:35 – Updated: 2026-08-05 08:47

Title

net: validate lwtstate->data before returning from skb_tunnel_info()

Summary

In the Linux kernel, the following vulnerability has been resolved: net: validate lwtstate->data before returning from skb_tunnel_info() skb_tunnel_info() returns pointer of lwtstate->data as ip_tunnel_info type without validation. lwtstate->data can have various types such as mpls_iptunnel_encap, etc and these are not compatible. So skb_tunnel_info() should validate before returning that pointer. Splat looks like: BUG: KASAN: slab-out-of-bounds in vxlan_get_route+0x418/0x4b0 [vxlan] Read of size 2 at addr ffff888106ec2698 by task ping/811 CPU: 1 PID: 811 Comm: ping Not tainted 5.13.0+ #1195 Call Trace: dump_stack_lvl+0x56/0x7b print_address_description.constprop.8.cold.13+0x13/0x2ee ? vxlan_get_route+0x418/0x4b0 [vxlan] ? vxlan_get_route+0x418/0x4b0 [vxlan] kasan_report.cold.14+0x83/0xdf ? vxlan_get_route+0x418/0x4b0 [vxlan] vxlan_get_route+0x418/0x4b0 [vxlan] [ ... ] vxlan_xmit_one+0x148b/0x32b0 [vxlan] [ ... ] vxlan_xmit+0x25c5/0x4780 [vxlan] [ ... ] dev_hard_start_xmit+0x1ae/0x6e0 __dev_queue_xmit+0x1f39/0x31a0 [ ... ] neigh_xmit+0x2f9/0x940 mpls_xmit+0x911/0x1600 [mpls_iptunnel] lwtunnel_xmit+0x18f/0x450 ip_finish_output2+0x867/0x2040 [ ... ]

Severity

7.8 (High)


                        
                          CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2024-05-23 19:12 UTC

Assigner

Linux mitre root Scorecard

References

8 references

URL	Tags
https://git.kernel.org/stable/c/e7f3c9df40515a6c6…
https://git.kernel.org/stable/c/b61d327cd3cc5ea59…
https://git.kernel.org/stable/c/83bdcfbd968bcc91a…
https://git.kernel.org/stable/c/8bb1589c89e61e3b1…
https://git.kernel.org/stable/c/8aa13a86964cdec4f…
https://git.kernel.org/stable/c/2179d96ec702cc33e…
https://git.kernel.org/stable/c/a915379594f1e0454…
https://git.kernel.org/stable/c/67a9c94317402b826…

Impacted products

2 products

Vendor	Product	Version
Linux	Linux	Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < e7f3c9df40515a6c6b46f36c4c94cf48a043f887 (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < b61d327cd3cc5ea591f3bf751dd11e034f388bb5 (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < 83bdcfbd968bcc91a0632b7b625e4a9b0cba5e0d (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < 8bb1589c89e61e3b182dd546f1021928ebb5c2a6 (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < 8aa13a86964cdec4fd969ef677c6614ff068641a (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < 2179d96ec702cc33ead02a9ce40ece599b8538c5 (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < a915379594f1e045421635c6316d8f3ffa018c58 (git) Affected: 61adedf3e3f1d3f032c5a6a299978d91eff6d555 , < 67a9c94317402b826fc3db32afc8f39336803d97 (git)
Linux	Linux	Affected: 4.3 Unaffected: 0 , < 4.3 (semver) Unaffected: 4.4.277 , ≤ 4.4.* (semver) Unaffected: 4.9.277 , ≤ 4.9.* (semver) Unaffected: 4.14.241 , ≤ 4.14.* (semver) Unaffected: 4.19.199 , ≤ 4.19.* (semver) Unaffected: 5.4.135 , ≤ 5.4.* (semver) Unaffected: 5.10.53 , ≤ 5.10.* (semver) Unaffected: 5.13.5 , ≤ 5.13.* (semver) Unaffected: 5.14 , ≤ * (original_commit_for_fix)

Show details on NVD website

JSON

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Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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EUVD-2026-344452

CVE-2021-47309 (GCVE-0-2021-47309)

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Nomenclature

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