In the Linux kernel, the following vulnerability has been resolved: net: use skb_header_pointer() for TCPv4 GSO frag_off check Syzbot reported a KMSAN uninit-value warning in gso_features_check() called from netif_skb_features() [1]. gso_features_check() reads iph->frag_off to decide whether to clear mangleid_features. Accessing the IPv4 header via ip_hdr()/inner_ip_hdr() can rely on skb header offsets that are not always safe for direct dereference on packets injected from PF_PACKET paths. Use skb_header_pointer() for the TCPv4 frag_off check so the header read is robust whether data is already linear or needs copying. [1] https://syzkaller.appspot.com/bug?extid=1543a7d954d9c6d00407
CVE-2026-43036
CVSS base score
5.5 (v3.1)
Severity
MEDIUM
Attack vector
Local
Weakness
CWE-908
Last modified
October 30, 2026
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected products
linux linux kernel
References
- git.kernel.org
- git.kernel.org
- git.kernel.org Patch
- git.kernel.org Patch
- git.kernel.org Patch
- git.kernel.org Patch