wifi: mwifiex: use the subframe length when parsing A-MSDU TDLS frames
Summary
| CVE | CVE-2026-74488 |
|---|---|
| State | PUBLISHED |
| Assigner | Linux |
| Source Priority | CVE Program / NVD first with legacy fallback |
| Published | 2026-08-15 13:17:53 UTC |
| Updated | 2026-08-19 17:21:05 UTC |
| Description | In the Linux kernel, the following vulnerability has been resolved: wifi: mwifiex: use the subframe length when parsing A-MSDU TDLS frames mwifiex_11n_dispatch_amsdu_pkt() splits an A-MSDU with ieee80211_amsdu_to_8023s() and walks the resulting subframes. For each subframe it passes the subframe data pointer to mwifiex_process_tdls_action_frame(), but pairs it with skb->len, the length of the A-MSDU parent, instead of rx_skb->len: rx_skb = __skb_dequeue(&list); rx_hdr = (struct rx_packet_hdr *)rx_skb->data; if (ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info) && ntohs(rx_hdr->eth803_hdr.h_proto) == ETH_P_TDLS) { mwifiex_process_tdls_action_frame(priv, (u8 *)rx_hdr, skb->len); } The parent is not a valid description of that buffer, and may not be valid memory at all. ieee80211_amsdu_to_8023s() ends with if (!reuse_skb) dev_kfree_skb(skb); and it only sets reuse_skb when the parent is linear, is not a head_frag, and is being consumed as the *last* subframe. So when the parent does not qualify for reuse it has already been freed, and the read of skb->len is a use-after-free. When it is reused, skb->len is the length of the last subframe, applied to every earlier subframe, which over-states the buffer whenever an earlier subframe is shorter. The callee cannot absorb a wrong length, because it derives its own ceiling from the value it is given. Each frame type computes ies_len = len - sizeof(struct ethhdr) - TDLS_*_FIX_LEN; and the element walk is then bounded entirely against that ceiling, for (end = pos + ies_len; pos + 1 < end; pos += 2 + pos[1]) { u8 ie_len = pos[1]; if (pos + 2 + ie_len > end) break; so a too-large len moves end past the end of the subframe and the walk reads and copies beyond it. The A-MSDU layout is chosen by the sender, which makes the difference between the last subframe and a shorter earlier one remotely selectable. Reaching this requires TDLS support in firmware and the TDLS ethertype on the subframe. The other caller, mwifiex_process_rx_packet(), is correct: it passes a pointer and a length that describe the same region of the RX buffer. Pass rx_skb->len, the length of the subframe actually being parsed. |
Risk And Classification
Primary CVSS: v3.1 8.8 HIGH from 416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS: 0.002470000 probability, percentile 0.162440000 (date 2026-08-19)
| Version | Source | Type | Score | Severity | Vector |
|---|---|---|---|---|---|
| 3.1 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | Secondary | 8.8 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| 3.1 | CNA | DECLARED | 8.8 | HIGH | CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
CVSS v3.1 Breakdown
Attack Vector
AdjacentAttack Complexity
LowPrivileges Required
NoneUser Interaction
NoneScope
UnchangedConfidentiality
HighIntegrity
HighAvailability
HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Vendor Declared Affected Products
| Source | Vendor | Product | Version | Platforms |
|---|---|---|---|---|
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 707664027bb9307f7268eda403af7c4ccd9b8644 git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 3b02275833a0d3e6583627995d614fa99bdf364f git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 a1f0f7dc7eb15754e6931b433edb7beb754c996a git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 25e5a3fe4f15e30f74eca42cbf3bcc3a3fbeda79 git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 ece2ebb34247d573142617dfc534a9dc11ba59be git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 c9dcfe6b8b71369e1d732e2ff622c3696a2f032c git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 5a21ab03829cb6d2682c127f22e2b9cd63b4393f git | Not specified |
| CNA | Linux | Linux | affected 776f742040ca5eb6242c60f29ac73d5752a5b621 99a948382af8a225e2d5e54a7052158cd6281cc6 git | Not specified |
| CNA | Linux | Linux | affected 4.5 | Not specified |
| CNA | Linux | Linux | unaffected 4.5 semver | Not specified |
| CNA | Linux | Linux | unaffected 5.10.265 5.10.* semver | Not specified |
| CNA | Linux | Linux | unaffected 5.15.216 5.15.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.1.183 6.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.6.151 6.6.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.12.103 6.12.* semver | Not specified |
| CNA | Linux | Linux | unaffected 6.18.44 6.18.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.1.8 7.1.* semver | Not specified |
| CNA | Linux | Linux | unaffected 7.2 * original_commit_for_fix | Not specified |
References
| Reference | Source | Link | Tags |
|---|---|---|---|
| git.kernel.org/stable/c/a1f0f7dc7eb15754e6931b433edb7beb754c996a | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/ece2ebb34247d573142617dfc534a9dc11ba59be | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/5a21ab03829cb6d2682c127f22e2b9cd63b4393f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/3b02275833a0d3e6583627995d614fa99bdf364f | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/707664027bb9307f7268eda403af7c4ccd9b8644 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/25e5a3fe4f15e30f74eca42cbf3bcc3a3fbeda79 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/99a948382af8a225e2d5e54a7052158cd6281cc6 | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| git.kernel.org/stable/c/c9dcfe6b8b71369e1d732e2ff622c3696a2f032c | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 | git.kernel.org | |
| CVE Program record | CVE.ORG | www.cve.org | canonical |
| NVD vulnerability detail | NVD | nvd.nist.gov | canonical, analysis |
No vendor comments have been submitted for this CVE.
There are currently no legacy QID mappings associated with this CVE.