{"cve":"CVE-2026-74488","nvd":{"published":"2026-08-15T13:17:53.690","modified":"2026-10-16T20:17:31.617","status":"Received","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nwifi: mwifiex: use the subframe length when parsing A-MSDU TDLS frames\n\nmwifiex_11n_dispatch_amsdu_pkt() splits an A-MSDU with\nieee80211_amsdu_to_8023s() and walks the resulting subframes. For each\nsubframe it passes the subframe data pointer to\nmwifiex_process_tdls_action_frame(), but pairs it with skb->len, the\nlength of the A-MSDU parent, instead of rx_skb->len:\n\n\trx_skb = __skb_dequeue(&list);\n\trx_hdr = (struct rx_packet_hdr *)rx_skb->data;\n\tif (ISSUPP_TDLS_ENABLED(priv->adapter->fw_cap_info) &&\n\t    ntohs(rx_hdr->eth803_hdr.h_proto) == ETH_P_TDLS) {\n\t\tmwifiex_process_tdls_action_frame(priv, (u8 *)rx_hdr,\n\t\t\t\t\t\t  skb->len);\n\t}\n\nThe parent is not a valid description of that buffer, and may not be\nvalid memory at all. ieee80211_amsdu_to_8023s() ends with\n\n\tif (!reuse_skb)\n\t\tdev_kfree_skb(skb);\n\nand it only sets reuse_skb when the parent is linear, is not a\nhead_frag, and is being consumed as the *last* subframe. So when the\nparent does not qualify for reuse it has already been freed, and the\nread of skb->len is a use-after-free. When it is reused, skb->len is\nthe length of the last subframe, applied to every earlier subframe,\nwhich over-states the buffer whenever an earlier subframe is shorter.\n\nThe callee cannot absorb a wrong length, because it derives its own\nceiling from the value it is given. Each frame type computes\n\n\ties_len = len - sizeof(struct ethhdr) - TDLS_*_FIX_LEN;\n\nand the element walk is then bounded entirely against that ceiling,\n\n\tfor (end = pos + ies_len; pos + 1 < end; pos += 2 + pos[1]) {\n\t\tu8 ie_len = pos[1];\n\n\t\tif (pos + 2 + ie_len > end)\n\t\t\tbreak;\n\nso a too-large len moves end past the end of the subframe and the walk\nreads and copies beyond it. The A-MSDU layout is chosen by the sender,\nwhich makes the difference between the last subframe and a shorter\nearlier one remotely selectable. Reaching this requires TDLS support in\nfirmware and the TDLS ethertype on the subframe.\n\nThe other caller, mwifiex_process_rx_packet(), is correct: it passes a\npointer and a length that describe the same region of the RX buffer.\n\nPass rx_skb->len, the length of the subframe actually being parsed.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","score":8.8},"cwes":[],"references":["https://git.kernel.org/stable/c/25e5a3fe4f15e30f74eca42cbf3bcc3a3fbeda79","https://git.kernel.org/stable/c/3b02275833a0d3e6583627995d614fa99bdf364f","https://git.kernel.org/stable/c/5a21ab03829cb6d2682c127f22e2b9cd63b4393f","https://git.kernel.org/stable/c/707664027bb9307f7268eda403af7c4ccd9b8644","https://git.kernel.org/stable/c/99a948382af8a225e2d5e54a7052158cd6281cc6"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:10.689564601+00:00"},"epss":{"cve":"CVE-2026-74488","score":0.00255,"percentile":0.16922,"date":"2026-10-25"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}