{"id":"CVE-2026-90018","state":"PUBLISHED","title":"staging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()","description":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()\n\nrtw_get_wps_attr() walks WPS attributes inside a WPS IE taken from\na wireless management frame. For each candidate attribute it only\nchecks that the fixed 4-byte attribute header (2-byte ID + 2-byte\nlength) fits inside the IE:\n\n\tif (attr_ptr + 4 > wps_ie + wps_ielen)\n\t\tbreak;\n\tu16 attr_id = get_unaligned_be16(attr_ptr);\n\tu16 attr_data_len = get_unaligned_be16(attr_ptr + 2);\n\tu16 attr_len = attr_data_len + 4;\n\nattr_data_len (and therefore attr_len) is read directly from the\nwire and is never checked against the remaining bytes in the IE\nbefore being used as the size of:\n\n\tmemcpy(buf_attr, attr_ptr, attr_len);\n\nSince attr_len is fully attacker controlled (0 to 65535+4), this is\nboth a heap OOB read of wps_ie, and, more seriously, a stack buffer\noverflow at several call sites where buf_attr is a single-byte\nstack variable, e.g. rtw_get_wps_attr_content()'s callers passing\nWPS_ATTR_SELECTED_REGISTRAR into a stack \"u8 sr\"/\"u8\nselected_registrar\" (drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c,\ndrivers/staging/rtl8723bs/core/rtw_mlme_ext.c). A crafted WPS IE in a\nbeacon or probe response processed during scanning can therefore\nsmash the stack of the parsing thread.\n\nrtw_get_wps_attr_content() itself has no independent length check\nand simply trusts the attr_len it gets back from rtw_get_wps_attr(),\nso fixing the bound here also fixes that caller.\n\nThe \"attr_ptr + 4 > wps_ie + wps_ielen\" header check above was added\nby commit 1463ca3ec6601 (\"staging: rtl8723bs: fix OOB reads in\nrtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get_wps_attr()\"), which\nbounded the fixed header but never extended the check to cover the\nvariable-length attribute data that follows it. Add that missing\ncheck before attr_len is used as a memcpy() length or accepted as a\nmatch.","publishedAt":"2026-09-16T10:33:23.489Z","updatedAt":"2026-10-19T08:56:31.878Z","severity":{"score":8.8,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"Linux"},"assigner":"Linux","products":["Linux Linux"],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"931640dfcb8cfa08f6cfb46229716d8072356420","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"3a6457ebf39080b87c712657fdb38f34a24fc3ff","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"fd5e24ea8373347d0352f153a66e8647337d1b10","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"a53d1ac9ce63db07943b2b2248111003851fb00f","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"ff61aa3289355dafa811550a1764691cd1f5d33b","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"34f51d196c43a42046d229de5e79025d5ca553ca","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"99aa998dec83ba180822f70e6d48a514fc81c20d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/staging/rtl8723bs/core/rtw_ieee80211.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.12","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/staging/rtl8723bs/core/rtw_ieee80211.c"]}],"references":["https://git.kernel.org/stable/c/931640dfcb8cfa08f6cfb46229716d8072356420","https://git.kernel.org/stable/c/3a6457ebf39080b87c712657fdb38f34a24fc3ff","https://git.kernel.org/stable/c/fd5e24ea8373347d0352f153a66e8647337d1b10","https://git.kernel.org/stable/c/a53d1ac9ce63db07943b2b2248111003851fb00f","https://git.kernel.org/stable/c/ff61aa3289355dafa811550a1764691cd1f5d33b","https://git.kernel.org/stable/c/34f51d196c43a42046d229de5e79025d5ca553ca","https://git.kernel.org/stable/c/99aa998dec83ba180822f70e6d48a514fc81c20d"],"weaknesses":[],"ingestedAt":"2026-10-29T20:13:34.582Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/90xxx/CVE-2026-90018.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-90018","state":"PUBLISHED","datePublished":"2026-09-16T10:33:23.489Z","dateUpdated":"2026-10-19T08:56:31.878Z","assignerShortName":"Linux","assignerOrgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateReserved":"2026-09-11T19:38:34.781Z"},"containers":{"cna":{"title":"staging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()","descriptions":[{"lang":"en","value":"In the Linux kernel, the following vulnerability has been resolved:\n\nstaging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()\n\nrtw_get_wps_attr() walks WPS attributes inside a WPS IE taken from\na wireless management frame. For each candidate attribute it only\nchecks that the fixed 4-byte attribute header (2-byte ID + 2-byte\nlength) fits inside the IE:\n\n\tif (attr_ptr + 4 > wps_ie + wps_ielen)\n\t\tbreak;\n\tu16 attr_id = get_unaligned_be16(attr_ptr);\n\tu16 attr_data_len = get_unaligned_be16(attr_ptr + 2);\n\tu16 attr_len = attr_data_len + 4;\n\nattr_data_len (and therefore attr_len) is read directly from the\nwire and is never checked against the remaining bytes in the IE\nbefore being used as the size of:\n\n\tmemcpy(buf_attr, attr_ptr, attr_len);\n\nSince attr_len is fully attacker controlled (0 to 65535+4), this is\nboth a heap OOB read of wps_ie, and, more seriously, a stack buffer\noverflow at several call sites where buf_attr is a single-byte\nstack variable, e.g. rtw_get_wps_attr_content()'s callers passing\nWPS_ATTR_SELECTED_REGISTRAR into a stack \"u8 sr\"/\"u8\nselected_registrar\" (drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c,\ndrivers/staging/rtl8723bs/core/rtw_mlme_ext.c). A crafted WPS IE in a\nbeacon or probe response processed during scanning can therefore\nsmash the stack of the parsing thread.\n\nrtw_get_wps_attr_content() itself has no independent length check\nand simply trusts the attr_len it gets back from rtw_get_wps_attr(),\nso fixing the bound here also fixes that caller.\n\nThe \"attr_ptr + 4 > wps_ie + wps_ielen\" header check above was added\nby commit 1463ca3ec6601 (\"staging: rtl8723bs: fix OOB reads in\nrtw_get_sec_ie(), rtw_get_wapi_ie(), and rtw_get_wps_attr()\"), which\nbounded the fixed header but never extended the check to cover the\nvariable-length attribute data that follows it. Add that missing\ncheck before attr_len is used as a memcpy() length or accepted as a\nmatch."}],"affected":[{"vendor":"Linux","product":"Linux","defaultStatus":"unaffected","versions":[{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"931640dfcb8cfa08f6cfb46229716d8072356420","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"3a6457ebf39080b87c712657fdb38f34a24fc3ff","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"fd5e24ea8373347d0352f153a66e8647337d1b10","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"a53d1ac9ce63db07943b2b2248111003851fb00f","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"ff61aa3289355dafa811550a1764691cd1f5d33b","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"34f51d196c43a42046d229de5e79025d5ca553ca","versionType":"git"},{"version":"554c0a3abf216c991c5ebddcdb2c08689ecd290b","status":"affected","lessThan":"99aa998dec83ba180822f70e6d48a514fc81c20d","versionType":"git"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/staging/rtl8723bs/core/rtw_ieee80211.c"]},{"vendor":"Linux","product":"Linux","defaultStatus":"affected","versions":[{"version":"4.12","status":"affected"},{"version":"0","status":"unaffected","lessThan":"4.12","versionType":"semver"},{"version":"5.15.221","status":"unaffected","lessThanOrEqual":"5.15.*","versionType":"semver"},{"version":"6.1.188","status":"unaffected","lessThanOrEqual":"6.1.*","versionType":"semver"},{"version":"6.6.157","status":"unaffected","lessThanOrEqual":"6.6.*","versionType":"semver"},{"version":"6.12.110","status":"unaffected","lessThanOrEqual":"6.12.*","versionType":"semver"},{"version":"6.18.51","status":"unaffected","lessThanOrEqual":"6.18.*","versionType":"semver"},{"version":"7.2.5","status":"unaffected","lessThanOrEqual":"7.2.*","versionType":"semver"},{"version":"7.3","status":"unaffected","lessThanOrEqual":"*","versionType":"original_commit_for_fix"}],"repo":"https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git","programFiles":["drivers/staging/rtl8723bs/core/rtw_ieee80211.c"]}],"references":[{"url":"https://git.kernel.org/stable/c/931640dfcb8cfa08f6cfb46229716d8072356420"},{"url":"https://git.kernel.org/stable/c/3a6457ebf39080b87c712657fdb38f34a24fc3ff"},{"url":"https://git.kernel.org/stable/c/fd5e24ea8373347d0352f153a66e8647337d1b10"},{"url":"https://git.kernel.org/stable/c/a53d1ac9ce63db07943b2b2248111003851fb00f"},{"url":"https://git.kernel.org/stable/c/ff61aa3289355dafa811550a1764691cd1f5d33b"},{"url":"https://git.kernel.org/stable/c/34f51d196c43a42046d229de5e79025d5ca553ca"},{"url":"https://git.kernel.org/stable/c/99aa998dec83ba180822f70e6d48a514fc81c20d"}],"metrics":[{"cvssV3_1":{"version":"3.1","vectorString":"CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","baseScore":8.8,"baseSeverity":"HIGH"},"scenarios":[{"lang":"en","value":"AV:A - A nearby attacker injects a crafted 802.11 beacon or probe response carrying a malformed WPS IE; rtl8723bs receives it over SDIO during scan (OnBeacon/OnProbeRsp → collect_bss_info → rtw_cfg80211_inform_bss → rtw_get_wps_attr), so the attacker must be on the same WiFi radio segment.\nAC:L - The attacker fully controls the WPS attribute ID and the 16-bit length field and can reliably hit the parser on any scan; no race, rare config, or other condition outside the attacker’s control is required.\nPR:N - Beacons and probe responses are processed before any association or authentication with the attacker-controlled BSS, so no local account, capability, or WiFi credentials on the victim are required.\nUI:N - Phones, Atom laptops, and IoT devices with this chip perform background and NetworkManager scans without a per-attack user action; once the interface is scanning, the driver parses received management frames on its own.\nS:U - The overflow corrupts kernel stack and adjacent heap inside the rtl8723bs driver; impact stays in the host kernel security authority and does not cross a VM, container, or IOMMU boundary.\nC:H - attr_data_len is attacker-controlled (up to 65535) and is used as a memcpy length without bounding to the IE, so the copy reads far past the WPS IE into kernel heap and the resulting stack smash can be leveraged for further disclosure.\nI:H - rtw_get_wps_attr_content() memcpy’s the claimed payload into a 1-byte stack variable (u8 sr/selected_registrar) using the unchecked length, producing an attacker-sized stack overflow that can overwrite return addresses and enable kernel code execution.\nA:H - A multi-kilobyte (or wrapped near-4GB) stack smash in the scan/BSS-inform path trips stack canaries or corrupts kernel control data and causes an oops, panic, or hang of the victim device."}]}],"providerMetadata":{"shortName":"Linux","orgId":"416baaa9-dc9f-4396-8d5f-8c081fb06d67","dateUpdated":"2026-10-19T08:56:31.878Z"},"cpeApplicability":[{"nodes":[{"operator":"OR","negate":false,"cpeMatch":[{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"5.15.221"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.1.188"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.6.157"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.12.110"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"6.18.51"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"7.2.5"},{"vulnerable":true,"criteria":"cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*","versionStartIncluding":"4.12","versionEndExcluding":"7.3"}]}]}],"x_generator":{"engine":"bippy-1.2.0"}}}}}