CVE-2026-23204

EUVD-2026-5841
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
ProviderTypeBase ScoreAtk. VectorAtk. ComplexityPriv. RequiredVector
NISTPrimary
UNKNOWN
---
Awaiting analysis
This vulnerability is currently awaiting analysis.
Base Score
CVSS 3.x
EPSS Score
Percentile: 4%
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linux
bookworm
vulnerable
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vulnerable
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bullseye (security)
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sid
6.18.12-1
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trixie (security)
6.12.73-1
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