CVE-2026-80825 — wifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb
In the Linux kernel, the following vulnerability has been resolved: wifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb mt7925_usb_sdio_tx_prepare_skb() pushes a TX descriptor and a USB header onto every skb and assumes the headroom for them is already there. That holds for locally generated traffic, where mac80211 reserves hw->extra_tx_headroom, but forwarded frames are sent through ieee80211_8023_xmit(), which does not reserve it. Bridge a wired interface to an mt7925u AP and the first forwarded frame that arrives short panics the kernel: skbuff: skb_under_panic: len:415 put:4 tail:0x19b end:0x640 dev:wlan1 kernel BUG at net/core/skbuff.c:212! Call trace: skb_panic+0x58/0x60 (P) skb_push+0x58/0x60 mt7925_usb_sdio_tx_prepare_skb+0xf8/0x1b8 [mt7925_common] mt76u_tx_queue_skb+0xa0/0x1f8 [mt76_usb] __mt76_tx_queue_skb+0x54/0xe8 [mt76] mt76_txq_schedule.part.0+0x204/0x478 [mt76] mt76_txq_schedule_all+0x50/0x80 [mt76] mt792x_tx_worker+0x68/0x100 [mt792x_lib] __mt76_worker_fn+0x84/0x150 [mt76] Whether a given setup hits it depends on how much headroom the ingress netdev leaves in its rx skbs. Reproduced on a Raspberry Pi 5 bridging onboard ethernet to a Netgear A9000; originally reported on an MT7986 router running OpenWrt. Nick Morrow's testing on a Pi 4 (bcmgenet), which leaves more headroom, helped narrow the trigger to the ingress path. The same bug was fixed on mt7921 by commit 98c4d0abf5c4 ("mt76: mt7921: don't assume adequate headroom for SDIO headers"), but mt7925 was copied from mt7921 without the fix. Add the same guard here.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.2% (30-day exploitation probability)+1
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.
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 | ≥ c948b5da6bbec742b433138e3e3f9537a85af2e5 and < 9a72b180f0575e41471e088e09bddc4b73d6dee2≥ c948b5da6bbec742b433138e3e3f9537a85af2e5 and < 22edb6786127271aeba7abd30f152977c605c6a3≥ c948b5da6bbec742b433138e3e3f9537a85af2e5 and < 8d481f93588932a95f657671d4e1601b90d130cc≥ c948b5da6bbec742b433138e3e3f9537a85af2e5 and < e5e8fc11a7ac578f16079f855b7fffc1649d053c≥ c948b5da6bbec742b433138e3e3f9537a85af2e5 and < ef3e34874d2332d0f63e72c2c35ce5c93568c125version 6.7 | Vulnerable | CVE Program (cve.org) e CISA ADP |
EPSS over time FIRST
Oct 15, 2026 → Oct 27, 2026 · 12 reading(s) · max 0.17%
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.
Timeline
What happened to this CVE, newest first.
- 2026
- Record published
- Affected products added · linux/linux
- Source status changed · → Received
- Record created in this database
- CVE published
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
7 on the record
- git.kernel.org/stable/c/9a72b180f0575e41471e088e09bddc4b73d6dee2
- git.kernel.org/stable/c/22edb6786127271aeba7abd30f152977c605c6a3
- git.kernel.org/stable/c/8d481f93588932a95f657671d4e1601b90d130cc
- git.kernel.org/stable/c/ef3e34874d2332d0f63e72c2c35ce5c93568c125
- git.kernel.org/stable/c/e5e8fc11a7ac578f16079f855b7fffc1649d053c
- nvd.nist.gov/vuln/detail/CVE-2026-80825
- github.com/advisories/GHSA-82xc-6pqj-mvc4
Elsewhere on this site
Related CVEs (same products)
- Unknown CVE-2026-99100 wifi: p54: validate firmware record lengths 5h
- Unknown CVE-2026-99092 riscv: patch: fix handling of bpf-jit execmem addresses 1d
- Unknown CVE-2026-99093 mm: don't schedule deferred kernel page table freeing while booting 1d
- Unknown CVE-2026-99095 drm/vc4: drain the hangcheck timer and works on V3D unbind 1d
- Unknown CVE-2026-99096 io_uring/register: don't exempt disabled rings from task restrictions 1d
- Unknown CVE-2026-99097 tee: shm: reject zero-sized allocations in tee_dyn_shm_alloc_helper() 1d
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-2026-80825 is "wifi: mt76: mt7925: ensure tx headroom in usb_sdio_tx_prepare_skb", 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 0.17% 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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