net: packet: fix wrong transport_header when sending VLAN-tagged frame
Summary
| CVE | CVE-2026-80906 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-09-04 18:18:00 UTC |
| Updated | 2026-09-04 18:18:00 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: net: packet: fix wrong transport_header when sending VLAN-tagged frame In packet_parse_headers(), when processing a VLAN-tagged frame, skb_set_network_header() is called to advance network_header past the VLAN tag to the inner protocol header. skb_probe_transport_header() is then called with skb->protocol still set to the outer VLAN EtherType (e.g. ETH_P_8021Q), while nhoff (derived from skb_network_offset()) already points past the VLAN tag to the inner protocol header. In __skb_flow_dissect(), proto is initialized to ETH_P_8021Q and nhoff points past the VLAN tag. When the dissector hits case ETH_P_8021Q, it reads a struct vlan_hdr at nhoff via __skb_header_pointer(), but that offset contains the inner protocol header (e.g. an IP header). The bytes are misinterpreted as a VLAN header, yielding a garbage encapsulated EtherType that matches no known protocol. The dissector returns false, so skb_probe_transport_header() never calls skb_set_transport_header(), leaving transport_header at its uninitialized sentinel value (~0U). Move skb_probe_transport_header() to before skb_set_network_header(). At the time skb_probe_transport_header() is called, network_header still points to the VLAN header, so nhoff correctly points to the VLAN header. The flow dissector can then parse the VLAN header, extract the inner EtherType, and advance nhoff to the inner protocol header, allowing transport_header to be set correctly. |
Risk And Classification
EPSS: 0.001650000 probability, percentile 0.059530000 (date 2026-09-07)
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected c2137d565ceb505de69593c181a0543bc4083838 a4b82de96d465ddb44bc931145c0fa80c4fe9c9c git | Not specified |
| CNA | Linux | Linux | affected 9ff46c36df2e0a1ac352f2f4038eaf3f0f7361b8 fa86bc52ea8ba981f74f851fd61e2a3d3bc0feac git | Not specified |
| CNA | Linux | Linux | affected dfed913e8b55a0c2c4906f1242fd38fd9a116e49 5479eb9b355f44745d7ccfe112386bd4f96eceea git | Not specified |
| CNA | Linux | Linux | affected dfed913e8b55a0c2c4906f1242fd38fd9a116e49 e451e20adb869a983a21dda158625f024142e61f git | Not specified |
| CNA | Linux | Linux | affected dfed913e8b55a0c2c4906f1242fd38fd9a116e49 6971cf319263d6a1b4096f9248aca9e57d77a1eb git | Not specified |
| CNA | Linux | Linux | affected dfed913e8b55a0c2c4906f1242fd38fd9a116e49 f9297abbcaba760b7a7b9d63b839f607f738013e git | Not specified |
| CNA | Linux | Linux | affected dfed913e8b55a0c2c4906f1242fd38fd9a116e49 6386a6ffa2efba2965ed8e4fa303582c0b76a215 git | Not specified |
| CNA | Linux | Linux | affected dfed913e8b55a0c2c4906f1242fd38fd9a116e49 01fdecc0480d916c799dbee584833a4a37e94d06 git | Not specified |
| CNA | Linux | Linux | affected ad3f90a9c4a2c74bb3711f2031bffda4ec44c849 git | Not specified |
| CNA | Linux | Linux | affected 5.10.163 5.10.266 semver | Not specified |
| CNA | Linux | Linux | affected 5.15.87 5.15.217 semver | Not specified |
| CNA | Linux | Linux | affected 5.4.229 5.5 semver | Not specified |
| CNA | Linux | Linux | affected 5.19 | Not specified |
| CNA | Linux | Linux | unaffected 5.19 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.266 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.217 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.184 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.153 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.105 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.46 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.10 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/5479eb9b355f44745d7ccfe112386bd4f96eceea | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/fa86bc52ea8ba981f74f851fd61e2a3d3bc0feac | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/6386a6ffa2efba2965ed8e4fa303582c0b76a215 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/6971cf319263d6a1b4096f9248aca9e57d77a1eb | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/f9297abbcaba760b7a7b9d63b839f607f738013e | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/01fdecc0480d916c799dbee584833a4a37e94d06 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/a4b82de96d465ddb44bc931145c0fa80c4fe9c9c | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/e451e20adb869a983a21dda158625f024142e61f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.