{"apiVersion":"1.0","identifier":"CVE-2026-74684","description":"In the Linux kernel, the following vulnerability has been resolved: net: tap: set skb->dev before parsing virtio net header in tap_get_user_xdp() The commit 4f61f133f354 (-net: tap: NULL pointer derefence in dev_parse_header_protocol when skb->dev is null-) fixed a crash in tap_get_user() by assigning skb->dev before calling tun_vnet_hdr_to_skb(). This is required because virtio_net_hdr_to_skb() may invoke dev_parse_header_protocol(), which dereferences skb->dev. Without the assignment, a NULL pointer dereference can occur. However, tap_get_user_xdp() still parses the virtio-net header before assigning skb->dev. When the vhost TX path passes an XDP buffer containing a GSO virtio-net header but the protocol is set to zero on purpose, tun_vnet_hdr_to_skb() can reach dev_parse_header_protocol() while skb->dev is still NULL, resulting in a crash. Fix this by looking up the tap device and assigning skb->dev before calling tun_vnet_hdr_to_skb(), matching the ordering already used in tap_get_user(). Preserve the existing RCU read-side critical section across dev_queue_xmit().","publishedAt":"2026-08-22T16:16:42","lastModifiedAt":"2026-08-25T06:18:51","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-74684","cvssScore":7.1,"cvssVector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H","epssProbability":0.00138,"riskScore":0.72,"affectedProduct":"linux","affectedVersions":"unknown","vulnerabilityType":"Kernel","operatingSystems":[],"links":{"self":"https://www.redsauce.net/api/cves/CVE-2026-74684","webPages":{"es":"https://www.redsauce.net/es/cves/CVE-2026-74684","en":"https://www.redsauce.net/en/cves/CVE-2026-74684","fr":"https://www.redsauce.net/fr/cves/CVE-2026-74684","pt":"https://www.redsauce.net/pt/cves/CVE-2026-74684","de":"https://www.redsauce.net/de/cves/CVE-2026-74684","sk":"https://www.redsauce.net/sk/cves/CVE-2026-74684","el":"https://www.redsauce.net/el/cves/CVE-2026-74684"},"source":"https://nvd.nist.gov/vuln/detail/CVE-2026-74684"}}