In the Linux kernel, the following vulnerability has been resolved: ipv6: sit: reload inner IPv6 header after GSO offloads ipip6_tunnel_xmit() caches the inner IPv6 header pointer at function entry and continues using it after iptunnel_handle_offloads(). For GSO skbs, iptunnel_handle_offloads() calls skb_header_unclone(). When the skb header is cloned, skb_header_unclone() can call pskb_expand_head(), which may move the skb head. The pskb_expand_head() contract requires pointers into the skb header to be reloaded after the call. If the later skb_realloc_headroom() branch is not taken, SIT uses the stale iph6 pointer to read the inner hop limit and DS field. That can read from a freed skb head after the old head's remaining clone is released. Reload iph6 after the offload helper succeeds and before subsequent reads from the inner IPv6 header. Keep the existing reload after skb_realloc_headroom(), since that branch can also replace the skb.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | NETWORK |
|---|---|
| Attack Complexity | LOW |
| Privileges Required | NONE |
| User Interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality Impact | HIGH |
| Integrity Impact | HIGH |
| Availability Impact | HIGH |
Source: 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Type: Secondary
Exploitability Score: 3.9
Impact Score: 5.9
| Source | Type | Description |
|---|---|---|
| [email protected] | Primary |
en
NVD-CWE-noinfo
|
| Vendor | Product | Version | Update | Type |
|---|---|---|---|---|
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd2a2248600> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd34122c480> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd36945ed80> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd3401d0540> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd2a2248fc0> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd39c4a5200> | Operating System |
| linux | linux_kernel | * | <built-in method update of dict object at 0x7fd319c75d00> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd3401d0e40> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd3401d2b40> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd2a2248d40> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd39c4a4040> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd319c75280> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd36945d180> | Operating System |
| linux | linux_kernel | 7.1 | <built-in method update of dict object at 0x7fd36945eac0> | Operating System |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc1:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc2:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc3:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc4:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc5:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc6:*:*:*:*:*:* |
| Yes | cpe:2.3:o:linux:linux_kernel:7.1:rc7:*:*:*:*:*:* |