CVE-2026-23204
High
net/sched: cls_u32: use skb_header_pointer_careful()
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_u32: use skb_header_pointer_careful() skb_header_pointer() does not fully validate negative @offset values. Use skb_header_pointer_careful() instead. GangMin Kim provided a report and a repro fooling u32_classify(): BUG: KASAN: slab-out-of-bounds in u32_classify+0x1180/0x11b0 net/sched/cls_u32.c:221
Exploit probability
0.1%
Published
February 14, 2026
Required by
Not available
Last source change
August 12, 2026
02 / AFFECTED SOFTWARE
Affected packages
03 / CONNECTIONS
Connected vulnerabilities
04 / EVIDENCE
Source records
Open Source Vulnerabilities
CVE-2026-23204
View original source
In the Linux kernel, the following vulnerability has been resolved: net/sched: cls_u32: use skb_header_pointer_careful() skb_header_pointer() does not fully validate negative @offset values. Use skb_header_pointer_careful() instead. GangMin Kim provided a report and a repro fooling u32_classify(): BUG: KASAN: slab-out-of-bounds in u32_classify+0x1180/0x11b0 net/sched/cls_u32.c:221
05 / REFERENCES
Further evidence
- https://cert-portal.siemens.com/productcert/html/ssa-019113.html
- https://cert-portal.siemens.com/productcert/html/ssa-082556.html
- https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
- https://git.kernel.org/stable/c/13336a6239b9d7c6e61483017bb8bdfe3ceb10a5
- https://git.kernel.org/stable/c/29681ed51e737be14d18ecd1c304c57002e4b72c
- https://git.kernel.org/stable/c/66e4b63d61c15de6ca5332d9ca6db59a404d7136
- https://git.kernel.org/stable/c/8a672f177ebe19c93d795fbe967846084fbc7943
- https://git.kernel.org/stable/c/cabd1a976375780dabab888784e356f574bbaed8
- https://git.kernel.org/stable/c/cfa745830e45ecb75c061aa34330ee0cac941cc7
- https://git.kernel.org/stable/c/e41a23e61259f5526af875c3b86b3d42a9bae0e5
- https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/23xxx/CVE-2026-23204.json
- https://nvd.nist.gov/vuln/detail/CVE-2026-23204