In the Linux kernel, the following vulnerability has been resolved: tap: fix stack info leak in tap_ioctl() SIOCGIFHWADDR In the SIOCGIFHWADDR path, tap_ioctl() copies 16 bytes of an uninitialised on-stack struct sockaddr_storage to userspace via ifr_hwaddr, but netif_get_mac_address() only writes sa_family and dev->addr_len (6 for Ethernet) bytes, leaving sa_data[6..13] uninitialised. Those 8 trailing bytes leak kernel stack contents; SIOCGIFHWADDR on a macvtap chardev returns kernel .text and direct-map pointers, defeating KASLR. Initialise ss at declaration.

A flaw was found in the Linux kernel's tap driver. This vulnerability allows an attacker to potentially disclose sensitive kernel stack memory contents to userspace. The flaw occurs in the `tap_ioctl()` function when handling the `SIOCGIFHWADDR` command, where uninitialized portions of a stack-allocated structure are copied to userspace. This information leak could be used to bypass Kernel Address Space Layout Randomization (KASLR), making it easier for attackers to exploit other vulnerabilities.

Red Hat Enterprise Linux 10 Fix deferred kernel Red Hat Enterprise Linux 6 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel Red Hat Enterprise Linux 7 Not affected kernel-rt Red Hat Enterprise Linux 8 Fix deferred kernel Red Hat Enterprise Linux 8 Fix deferred kernel-rt Red Hat Enterprise Linux 9 Fix deferred kernel Red Hat Enterprise Linux 9 Fix deferred kernel-rt https://www.cve.org/CVERecord?id=CVE-2026-52937 https://nvd.nist.gov/vuln/detail/CVE-2026-52937 https://lore.kernel.org/linux-cve-announce/2026062434-CVE-2026-52937-62eb@gregkh/T