Unknown

CVE-2026-90160 — lwt_bpf: Restore reserved headroom after xmit program

In the Linux kernel, the following vulnerability has been resolved: lwt_bpf: Restore reserved headroom after xmit program ip_finish_output2() expands an skb to LL_RESERVED_SPACE(dev) before LWT xmit. An LWT_XMIT BPF program can then modify the skb head and still return BPF_OK, so bpf_xmit() rechecks the remaining headroom before the skb continues to neighbour output. That recheck uses dst->dev->hard_header_len. This is not enough for the neighbour cached-header path: neigh_hh_output() copies the cached hardware header using the aligned hh_cache size, HH_DATA_MOD for short headers or HH_DATA_ALIGN(hh_len) otherwise. On Ethernet, hard_header_len is 14 but the cached copy needs 16 bytes. If an LWT_XMIT BPF program calls bpf_skb_change_head(skb, 1, 0), the skb can still have 15 bytes of headroom after the program. The existing check accepts that, after which neigh_hh_output() hits its headroom warning and drops the skb. Use LL_RESERVED_SPACE(dst->dev) in the post-BPF headroom check to match the reservation made before LWT xmit.

Published Sep 17, 2026 · Updated Oct 19, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP, GitHub Security Advisories · CNA: Linux

Low

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.

How the score was calculated

EPSS 0.2% (30-day exploitation probability)+2

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation

Not confirmed

Not in CISA KEV — an absence of record, not proof it is unexploited.

EPSS FIRST

0.21%

ahead of 11% of scored CVEs · Oct 20, 2026

Affects

Linux

CVSS base

—

Score not published yet.

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

No fix documented by the sources we poll. That does not mean none exists: check the vendor advisory.

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

Identify exposed assets running the affected vendor/product/version combinations (Linux Linux).
No fix documented in the sources: reduce exposure and monitor the vendor advisory.
Search available logs for exploit probes, errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

Vendor	Product	Versions	Status	Source
Linux	Linux	≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < 753e5cdcca5474d230d62bb3489e5168ab27c272≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < c488071c3441fa34f5a87cd6c12ce2cc6304f20e≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < a38c0eb447e2dd0120a2ebcdba470f9505ac8907≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < de2b2004e16f2930eb689175e2c1998b0a68d499≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < 7d043e24520a273c362be5dd7d9c82796879a49b≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < 7cf561843ed0ad57501892a65abb77957e6c800f≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < 179a5b2171573d94a25c9aa8e1c9f9ac352ad316≥ 3a0af8fd61f90920f6fa04e4f1e9a6a73c1b4fd2 and < 5fe7007aed9ad069b2bd77e5d0c875c64f5c0269 and 1 more version 4.10	Vulnerable	CVE Program (cve.org) e CISA ADP

EPSS over time FIRST

Oct 15, 2026 → Oct 20, 2026 · 5 reading(s) · max 0.21%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

Not enough vector or weakness data: use the affected application’s logs as a starting point.

application logs

Timeline

What happened to this CVE, newest first.

2026
Record published
Oct 15, 2026
Affected products added · linux/linux
Oct 15, 2026 · CVE Program (cve.org) e CISA ADP
Source status changed · → Received
Oct 15, 2026 · NIST National Vulnerability Database
Record created in this database
Oct 15, 2026 · NIST National Vulnerability Database
CVE published
Sep 17, 2026 · Linux

Source activity

Repeated readings are counted rather than listed.

1× References added · Oct 19, 2026 – Oct 19, 2026
1× Official description updated · Oct 15, 2026 – Oct 15, 2026

References

10 on the record

git.kernel.org/stable/c/a38c0eb447e2dd0120a2ebcdba470f9505ac8907
NIST National Vulnerability Database
git.kernel.org/stable/c/7cf561843ed0ad57501892a65abb77957e6c800f
NIST National Vulnerability Database
git.kernel.org/stable/c/179a5b2171573d94a25c9aa8e1c9f9ac352ad316
NIST National Vulnerability Database
git.kernel.org/stable/c/5fe7007aed9ad069b2bd77e5d0c875c64f5c0269
NIST National Vulnerability Database
git.kernel.org/stable/c/de2b2004e16f2930eb689175e2c1998b0a68d499
NIST National Vulnerability Database
nvd.nist.gov/vuln/detail/CVE-2026-90160
GitHub Security Advisories
git.kernel.org/stable/c/753e5cdcca5474d230d62bb3489e5168ab27c272
NIST National Vulnerability Database
git.kernel.org/stable/c/7d043e24520a273c362be5dd7d9c82796879a49b
NIST National Vulnerability Database
git.kernel.org/stable/c/c488071c3441fa34f5a87cd6c12ce2cc6304f20e
NIST National Vulnerability Database
github.com/advisories/GHSA-p997-jc38-xxh3
GitHub Security Advisories

Elsewhere on this site

Linux
every CVE for this vendor

Related CVEs (same products)

Unknown CVE-2026-98869 bpf: Infer zext_dst based on static register liveness analysis 6h
Unknown CVE-2023-7356 Bluetooth: ISO: Copy BASE if service data matches EIR_BAA_SERVICE_UUID 6h
Unknown CVE-2026-98866 sched/cache: Introduce task_struct->sched_cache_grp to fix UAF 3d
Unknown CVE-2026-98867 dm-pcache: bound the logical key offset from persistent memory 3d
Unknown CVE-2026-98868 dm-pcache: reject a kset that overruns its segment 3d
Unknown CVE-2026-98856 kprobes: Skip disarmed probes when checking optkprobe overlap 3d

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

No CVSS score published by NVD, the CNA, CISA or GitHub so far.
No fixed version, patch or mitigation documented.
No CISA SSVC assessment.
No CWE classification.
No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-90160 is "lwt_bpf: Restore reserved headroom after xmit program", rated Unknown. It affects Linux (Linux); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. EPSS 0.21% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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