https://vulnerability.circl.lu Contains only the most 10 recent entries. http://www.rssboard.org/rss-specification python-feedgen en Mon, 28 Sep 2026 20:20:29 +0000 https://vulnerability.circl.lu/vuln/fkie_cve-2026-98116 <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF</p> <p>snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation with an mmap_count check performed under the PCM stream lock, but the lock is released long before the buffer is actually freed: snd_pcm_sync_stop(), constraint refinement and do_free_pages() all happen in between. snd_pcm_mmap_data(), on the other hand, takes no lock at all: it validates against the old buffer&#39;s state and dma_bytes, remaps its pages into the VMA, and only then increments mmap_count.</p> <p>A concurrent mmap() can therefore slip in between the check and the free. remap_pfn_range() installs writable PTEs for the old buffer&#39;s pages without taking page references, and the subsequent do_free_pages() returns those pages to the page allocator while the VMA still maps them. This leaves a stale, writable mapping of freed pages: a page-level use-after-free that can be leveraged for local privilege escalation.</p> <p>Make snd_pcm_mmap_data() participate in the buffer-access scheme introduced for hw_params/hw_free: acquire runtime-&gt;buffer_accessing before validating and remapping, and release it afterwards. Buffer reallocation already fails with -EBUSY while accessors are active, and the mmap side now fails with -EBUSY while a reallocation is in progress, so the validate/remap sequence and the check/free sequence can no longer interleave.</p> <p>A reproducer that turns this rac…</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF</p> <p>snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation with an mmap_count check performed under the PCM stream lock, but the lock is released long before the buffer is actually freed: snd_pcm_sync_stop(), constraint refinement and do_free_pages() all happen in between. snd_pcm_mmap_data(), on the other hand, takes no lock at all: it validates against the old buffer&#39;s state and dma_bytes, remaps its pages into the VMA, and only then increments mmap_count.</p> <p>A concurrent mmap() can therefore slip in between the check and the free. remap_pfn_range() installs writable PTEs for the old buffer&#39;s pages without taking page references, and the subsequent do_free_pages() returns those pages to the page allocator while the VMA still maps them. This leaves a stale, writable mapping of freed pages: a page-level use-after-free that can be leveraged for local privilege escalation.</p> <p>Make snd_pcm_mmap_data() participate in the buffer-access scheme introduced for hw_params/hw_free: acquire runtime-&gt;buffer_accessing before validating and remapping, and release it afterwards. Buffer reallocation already fails with -EBUSY while accessors are active, and the mmap side now fails with -EBUSY while a reallocation is in progress, so the validate/remap sequence and the check/free sequence can no longer interleave.</p> <p>A reproducer that turns this rac…</p> https://vulnerability.circl.lu/vuln/fkie_cve-2026-98116 https://vulnerability.circl.lu/vuln/ghsa-pwf2-cf6j-p6wx <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF</p> <p>snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation with an mmap_count check performed under the PCM stream lock, but the lock is released long before the buffer is actually freed: snd_pcm_sync_stop(), constraint refinement and do_free_pages() all happen in between. snd_pcm_mmap_data(), on the other hand, takes no lock at all: it validates against the old buffer&#39;s state and dma_bytes, remaps its pages into the VMA, and only then increments mmap_count.</p> <p>A concurrent mmap() can therefore slip in between the check and the free. remap_pfn_range() installs writable PTEs for the old buffer&#39;s pages without taking page references, and the subsequent do_free_pages() returns those pages to the page allocator while the VMA still maps them. This leaves a stale, writable mapping of freed pages: a page-level use-after-free that can be leveraged for local privilege escalation.</p> <p>Make snd_pcm_mmap_data() participate in the buffer-access scheme introduced for hw_params/hw_free: acquire runtime-&gt;buffer_accessing before validating and remapping, and release it afterwards. Buffer reallocation already fails with -EBUSY while accessors are active, and the mmap side now fails with -EBUSY while a reallocation is in progress, so the validate/remap sequence and the check/free sequence can no longer interleave.</p> <p>A reproducer that turns this rac…</p> <p>In the Linux kernel, the following vulnerability has been resolved:</p> <p>ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF</p> <p>snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation with an mmap_count check performed under the PCM stream lock, but the lock is released long before the buffer is actually freed: snd_pcm_sync_stop(), constraint refinement and do_free_pages() all happen in between. snd_pcm_mmap_data(), on the other hand, takes no lock at all: it validates against the old buffer&#39;s state and dma_bytes, remaps its pages into the VMA, and only then increments mmap_count.</p> <p>A concurrent mmap() can therefore slip in between the check and the free. remap_pfn_range() installs writable PTEs for the old buffer&#39;s pages without taking page references, and the subsequent do_free_pages() returns those pages to the page allocator while the VMA still maps them. This leaves a stale, writable mapping of freed pages: a page-level use-after-free that can be leveraged for local privilege escalation.</p> <p>Make snd_pcm_mmap_data() participate in the buffer-access scheme introduced for hw_params/hw_free: acquire runtime-&gt;buffer_accessing before validating and remapping, and release it afterwards. Buffer reallocation already fails with -EBUSY while accessors are active, and the mmap side now fails with -EBUSY while a reallocation is in progress, so the validate/remap sequence and the check/free sequence can no longer interleave.</p> <p>A reproducer that turns this rac…</p> https://vulnerability.circl.lu/vuln/ghsa-pwf2-cf6j-p6wx https://vulnerability.circl.lu/vuln/ubuntu-cve-2026-98116 <p><strong>Affected:</strong> Ubuntu:Pro:14.04:LTS: linux, Ubuntu:Pro:14.04:LTS: linux-aws, Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:14.04:LTS: linux-lts-xenial, Ubuntu:Pro:16.04:LTS: linux, Ubuntu:Pro:16.04:LTS: linux-aws, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe and 246 more</p> <p>In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation with an mmap_count check performed under the PCM stream lock, but the lock is released long before the buffer is actually freed: snd_pcm_sync_stop(), constraint refinement and do_free_pages() all happen in between. snd_pcm_mmap_data(), on the other hand, takes no lock at all: it validates against the old buffer&#39;s state and dma_bytes, remaps its pages into the VMA, and only then increments mmap_count. A concurrent mmap() can therefore slip in between the check and the free. remap_pfn_range() installs writable PTEs for the old buffer&#39;s pages without taking page references, and the subsequent do_free_pages() returns those pages to the page allocator while the VMA still maps them. This leaves a stale, writable mapping of freed pages: a page-level use-after-free that can be leveraged for local privilege escalation. Make snd_pcm_mmap_data() participate in the buffer-access scheme introduced for hw_params/hw_free: acquire runtime-&gt;buffer_accessing before validating and remapping, and release it afterwards. Buffer reallocation already fails with -EBUSY while accessors are active, and the mmap side now fails with -EBUSY while a reallocation is in progress, so the validate/remap sequence and the check/free sequence can no longer interleave. A reproducer that turns this race int…</p> <p><strong>Affected:</strong> Ubuntu:Pro:14.04:LTS: linux, Ubuntu:Pro:14.04:LTS: linux-aws, Ubuntu:Pro:14.04:LTS: linux-azure, Ubuntu:Pro:14.04:LTS: linux-lts-xenial, Ubuntu:Pro:16.04:LTS: linux, Ubuntu:Pro:16.04:LTS: linux-aws, Ubuntu:Pro:16.04:LTS: linux-aws-hwe, Ubuntu:Pro:16.04:LTS: linux-azure, Ubuntu:Pro:16.04:LTS: linux-gcp, Ubuntu:Pro:16.04:LTS: linux-hwe and 246 more</p> <p>In the Linux kernel, the following vulnerability has been resolved: ALSA: pcm: Serialize PCM mmap with buffer reallocation to fix page UAF snd_pcm_hw_params() and snd_pcm_hw_free() guard buffer reallocation with an mmap_count check performed under the PCM stream lock, but the lock is released long before the buffer is actually freed: snd_pcm_sync_stop(), constraint refinement and do_free_pages() all happen in between. snd_pcm_mmap_data(), on the other hand, takes no lock at all: it validates against the old buffer&#39;s state and dma_bytes, remaps its pages into the VMA, and only then increments mmap_count. A concurrent mmap() can therefore slip in between the check and the free. remap_pfn_range() installs writable PTEs for the old buffer&#39;s pages without taking page references, and the subsequent do_free_pages() returns those pages to the page allocator while the VMA still maps them. This leaves a stale, writable mapping of freed pages: a page-level use-after-free that can be leveraged for local privilege escalation. Make snd_pcm_mmap_data() participate in the buffer-access scheme introduced for hw_params/hw_free: acquire runtime-&gt;buffer_accessing before validating and remapping, and release it afterwards. Buffer reallocation already fails with -EBUSY while accessors are active, and the mmap side now fails with -EBUSY while a reallocation is in progress, so the validate/remap sequence and the check/free sequence can no longer interleave. A reproducer that turns this race int…</p> https://vulnerability.circl.lu/vuln/ubuntu-cve-2026-98116 https://vulnerability.circl.lu/vuln/wid-sec-w-2026-3579 <p>Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Zustand herbeizuführen oder nicht näher spezifizierten Angriff durchzuführen.</p> <p>Ein lokaler Angreifer kann mehrere Schwachstellen im Linux Kernel ausnutzen, um einen Denial of Service Zustand herbeizuführen oder nicht näher spezifizierten Angriff durchzuführen.</p> https://vulnerability.circl.lu/vuln/wid-sec-w-2026-3579