https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Tue, 29 Sep 2026 22:06:20 +0000 https://vulnerability.circl.lu/vuln/cve-2026-90226 <p><strong>Affected:</strong> Linux</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>nfc: llcp: avoid userspace overflow on invalid optlen</p> <p>nfc_llcp_getsockopt() casts optval to (u32 __user *) for put_user(), so the kernel always stores 4 bytes regardless of the caller-supplied optlen. The existing min_t(u32, len, sizeof(u32)) only clamps the length reported back to userspace; it does not constrain the store. A call with optlen &lt; 4 therefore writes past the user buffer, violating the getsockopt(2) contract for all five supported optnames.</p> <p>Reject any call with optlen &lt; sizeof(u32) up front. &#39;len&#39; is int, so a plain size comparison would promote a negative optlen to size_t and slip past the check; an explicit &#39;len &lt; 0&#39; test is added first to catch negative values before the size compare.</p> <p><strong>Affected:</strong> Linux</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>nfc: llcp: avoid userspace overflow on invalid optlen</p> <p>nfc_llcp_getsockopt() casts optval to (u32 __user *) for put_user(), so the kernel always stores 4 bytes regardless of the caller-supplied optlen. The existing min_t(u32, len, sizeof(u32)) only clamps the length reported back to userspace; it does not constrain the store. A call with optlen &lt; 4 therefore writes past the user buffer, violating the getsockopt(2) contract for all five supported optnames.</p> <p>Reject any call with optlen &lt; sizeof(u32) up front. &#39;len&#39; is int, so a plain size comparison would promote a negative optlen to size_t and slip past the check; an explicit &#39;len &lt; 0&#39; test is added first to catch negative values before the size compare.</p> https://vulnerability.circl.lu/vuln/cve-2026-90226