Vulnerability in Linux kernel (CVE-2026-90018)
Summary
Vulnerability in Linux kernel (CVE-2026-90018). Successful exploitation can lead to full system takeover.
Original description
The description as published by the source.
In the Linux kernel, the following vulnerability has been resolved:
staging: rtl8723bs: fix OOB read / stack overflow in rtw_get_wps_attr()
rtw_get_wps_attr() walks WPS attributes inside a WPS IE taken from
a wireless management frame. For each candidate attribute it only
checks that the fixed 4-byte attribute header (2-byte ID + 2-byte
length) fits inside the IE:
if (attr_ptr + 4 > wps_ie + wps_ielen)
break;
u16 attr_id = get_unaligned_be16(attr_ptr);
u16 attr_data_len = get_unaligned_be16(attr_ptr + 2);
u16 attr_len = attr_data_len + 4;
attr_data_len (and therefore attr_len) is read directly from the
wire and is never checked against the remaining bytes in the IE
before being used as the size of:
memcpy(buf_attr, attr_ptr, attr_len);
Since attr_len is fully attacker controlled (0 to 65535+4), this is
both a heap OOB read of wps_ie, and, more seriously, a stack buffer
overflow at several call sites where buf_attr is a single-byte
stack variable, e.g. rtw_get_wps_attr_content()'s callers passing
WPS_ATTR_SELECTED_REGISTRAR into a stack "u8 sr"/"u8
selected_registrar" (drivers/staging/rtl8723bs/os_dep/ioctl_cfg80211.c,
drivers/staging/rtl8723bs/core/rtw_mlme_ext.c). A crafted WPS IE in a
beacon or probe response processed during scanning can therefore
smash the stack of the parsing thread.
rtw_get_wps_attr_content() itself has no independent length check
and simply trusts the attr_len it gets back from rtw_get_wps_attr(),
so fixing the bound here also fixes that…
Source: NIST National Vulnerability Database NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-90018 has been found in Linux kernel.
Successful exploitation can lead to full system takeover. CVSS score: 8.8/10.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Linux kernel CVE-2026-90018" on the vendor's site.
CVE-2026-90018 (Linux kernel) — CVSS v3 8.8
Attack vector: adjacent-network / unauthenticated / no user interaction
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (unclassified) exists in Linux kernel.
Check the vendor advisory for the affected versions of Linux kernel.
Severity: High (CVSS 8.8/10). Successful exploitation can lead to full system takeover.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Audit SBOM/dependencies to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
Audit SBOM/dependencies for affected components.資産台帳・SBOM・依存マニフェストで Linux kernel を使っているサービスとバージョンを洗い出す。
-
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2026-90018 linux Fixed in: 6.1.190-1
- Ubuntu UBUNTU-CVE-2026-90018 linux-azure
References
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web git.kernel.org
- web nvd.nist.gov
- web github.com