CVE-2026-72400
Received
Received - Intake
Buffer Length Validation Flaw in Linux Kernel SRH Handling
Vulnerability report for CVE-2026-72400, including description, CVSS score, EPSS score, affected products, exploitability, helpful resources, and attack-flow context.
Publication date: 2026-08-15
Last updated on: 2026-08-15
Assigner: kernel.org
Description
Description
In the Linux kernel, the following vulnerability has been resolved:
seg6: validate SRH length before reading fixed fields
seg6_validate_srh() reads fixed SRH fields such as srh->type and
srh->hdrlen before checking that the supplied length covers the fixed
struct ipv6_sr_hdr fields.
The BPF SEG6 encap path reaches this with a BPF program-supplied pointer
and length: bpf_lwt_push_encap() and the SEG6 local BPF END_B6 and
END_B6_ENCAP actions call bpf_push_seg6_encap(), which forwards the
length to seg6_validate_srh() with no minimum-size guard. A 2-byte SEG6
encap header can therefore make the validator read srh->type at offset 2
beyond the caller-supplied buffer.
Reject lengths shorter than the fixed SRH at the top of
seg6_validate_srh(), before any field is read. This fixes the BPF helper
path and keeps the common validator robust.
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| linux | linux_kernel | * |
Helpful Resources
Exploitability
CWE
KEV
| CWE ID | Description |
|---|---|
| CWE-UNKNOWN |
