CVE-2026-74650staging: rtl8723bs: fix OOB read in WMM_param_handler()

Official description

In the Linux kernel, the following vulnerability has been resolved: staging: rtl8723bs: fix OOB read in WMM_param_handler() WMM_param_handler() copies a fixed-size WMM parameter element out of a received information element without checking that the element is long enough, causing an out-of-bounds read for a short WMM IE. The handler reads sizeof(struct WMM_para_element) (18) bytes at pIE->data + 6, so it requires pIE->length to be at least 24 (WLAN_WMM_LEN), but it never validates the length. Two of its three callers reach it after matching only the WMM OUI: OnAssocRsp() in rtw_mlme_ext.c matches a 6-byte OUI, and join_cmd_hdl() matches a 4-byte OUI, before calling the handler. A vendor-specific IE carrying the WMM OUI but a length between 6 and 23, placed in an association response or in the IE blob handed to join_cmd_hdl(), passes the OUI check and then makes the memcmp() and memcpy() at pIE->data + 6 read past the end of the element. OnAssocRsp() parses a frame received from the AP, so this is reachable from a remote peer. The remaining caller in rtw_wlan_util.c already guards the handler with "pIE->length == WLAN_WMM_LEN". Move the equivalent check into the handler itself so every caller is covered; the sibling IE handlers in the same parsing loop (HT_caps_handler(), HT_info_handler(), ERP_IE_handler()) likewise bound their accesses by pIE->length.

Affected packages & fixed versions

Affected products (as reported)

References

• https://git.kernel.org/stable/c/5df2fd06567df5f178c8faae0bdaefd203618d21
• https://git.kernel.org/stable/c/6cdca4c8b64c15a3ab9ad7a85f482e9519eadf93
• https://git.kernel.org/stable/c/2bee6f7a0f0125238951e31da2e96d06fe359043
• https://git.kernel.org/stable/c/1158b9931207392d6dd136aa0c4be18893b50fa1
• https://git.kernel.org/stable/c/ce2399717de242344880044b91a20a712644fdfb
• https://git.kernel.org/stable/c/e5b7610008f4e6a80c8b071aa77ddbd5e17ea472
• https://git.kernel.org/stable/c/e429c6dfd5d2324cd866daaf4c29d5cfe4dea0e4
• https://git.kernel.org/stable/c/ae21407350151bddfd4fea7aa39bd0643c0ca9d3