{
  "affected": [
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:12",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:13",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    },
    {
      "ecosystem_specific": {
        "urgency": "not yet assigned"
      },
      "package": {
        "ecosystem": "Debian:14",
        "name": "linux"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "7.2.9-1"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "details": "In the Linux kernel, the following vulnerability has been resolved:  net: ipv6: keep room for the mac header in dst_dev_overhead()  The seg6, ioam6 and rpl lwtunnels size their skb_cow_head() request as the length they are about to push plus dst_dev_overhead(), then push the new headers and rebuild the mac header below them with skb_mac_header_rebuild().  That rebuild needs skb-\u003emac_len of headroom, but dst_dev_overhead() leaves LL_RESERVED_SPACE() of the egress device, 16 bytes for plain Ethernet.  Where the mac header is longer than that, as it is on ingress through a VLAN device with reorder_hdr off, the rebuild runs out of room: skb_set_mac_header(skb, -skb-\u003emac_len) computes a negative offset, stores it unchecked in the u16 skb-\u003emac_header, and the memmove that follows writes skb-\u003emac_len bytes about 64 KB past skb-\u003ehead. Forwarding plain ping6 traffic through such a device reproduces it on all five seg6 encapsulation modes and on the rpl and ioam6 inline paths; skb-\u003emac_header comes back as 65534 on a 704-byte head.  Return the larger of the two.  The helper already returns skb-\u003emac_len when it has no dst, so this only makes the other branch agree, and it covers every caller rather than each call site in turn.",
  "id": "DEBIAN-CVE-2026-98570",
  "modified": "2026-10-19T04:47:34.144601960Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://security-tracker.debian.org/tracker/CVE-2026-98570"
    }
  ],
  "upstream": [
    "CVE-2026-98570"
  ]
}