Vulnerability details
CVE-2026-68121
pppoe: reload header pointer after dev_hard_header()
Official description
In the Linux kernel, the following vulnerability has been resolved: pppoe: reload header pointer after dev_hard_header() pppoe_sendmsg() saves a pointer to the PPPoE header before calling dev_hard_header(). Device header callbacks are allowed to reallocate the skb head, invalidating pointers into it. This can happen when a send is blocked in copy_from_user() while the first non-Ethernet port is added to an empty team device. The team's delegated GRE header callback then expands the skb head. PPPoE subsequently writes six bytes through the stale pointer into the freed head. Reload the PPPoE header through the skb's network-header offset after device header creation. pskb_expand_head() updates that offset when it relocates the head.
CVSS scores
| Score | Version | Source | Vector |
|---|---|---|---|
| 7.8High | 3.1 | CVEProject cvelistV5 (CNA) (Linux) | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |
Affected products
| Vendor | Product | Versions | Source |
|---|---|---|---|
| Linux | Linux | 2.6.12 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < 6eed5ae7887a93160803d2b81ff88e75eefd4a4c | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < ba3409369c5413cdf0dcbf3a928f76b48e8c3e6a | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < e6493a4d1ee17595766165fa446d45b7e0c318d0 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < 7a56e7c9b08e08fd55a1bcada24cf4fe3782b722 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < 6866abf59976d273164a6624234d96a967280223 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < bed4caecd723693f750e13adbb2c42ca1249a3fd | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < e9c238f6fe42fb1b4dba3a578277de32cb487937 | CVEProject cvelistV5 (CNA) |
| Linux | Linux | 1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 ≤ v < 7e9fbd7f96bcde63a7c798fe16b38cedee7a1501 | CVEProject cvelistV5 (CNA) |
References and advisories
8- https://git.kernel.org/stable/c/7a56e7c9b08e08fd55a1bcada24cf4fe3782b722
- https://git.kernel.org/stable/c/6eed5ae7887a93160803d2b81ff88e75eefd4a4c
- https://git.kernel.org/stable/c/ba3409369c5413cdf0dcbf3a928f76b48e8c3e6a
- https://git.kernel.org/stable/c/e6493a4d1ee17595766165fa446d45b7e0c318d0
- https://git.kernel.org/stable/c/7e9fbd7f96bcde63a7c798fe16b38cedee7a1501
- https://git.kernel.org/stable/c/6866abf59976d273164a6624234d96a967280223
- https://git.kernel.org/stable/c/bed4caecd723693f750e13adbb2c42ca1249a3fd
- https://git.kernel.org/stable/c/e9c238f6fe42fb1b4dba3a578277de32cb487937
Details
- Published
- 2026-08-10
- Last updated
- 2026-10-20
- State
- Published
- Assigner (CNA)
- Linux
Exploit prediction (EPSS)
SSVC assessment (CISA)
- Automatable
- No
- Exploitation
- None
- Technical impact
- Total
Weaknesses (CWE)
- CWE-416Use After Free