CVE-2026-98116
HighCVSS 7.8Exploitation Probability (EPSS)
Low risk2th percentile - higher than 2% of all known CVEs
Summary
In the Linux kernel, a race condition exists in the ALSA subsystem between snd_pcm_mmap_data() and PCM buffer reallocation in snd_pcm_hw_params()/snd_pcm_hw_free(). Because mmap takes no lock, it can map pages of the old buffer that are subsequently freed back to the page allocator, leaving a stale, writable mapping of freed memory (a page-level use-after-free).
Risk Assessment
This page-level use-after-free can be leveraged by a local user for privilege escalation. Exploitation requires the ability to invoke ALSA PCM operations and concurrent mmap, which narrows the set of potential attackers.
Recommendation
Update the Linux kernel to a version containing the fix that serializes snd_pcm_mmap_data() with buffer reallocation via the buffer_accessing mechanism. Until the patch is applied, restrict access to ALSA/PCM devices for untrusted local users.
Related vulnerabilities
- CVE-2026-117691Critical
A flaw was found in the SAML HTTP-Redirect binding implementation of Keycloak. The issue occurs because the server processes percent-encoded parameter names (like %53AMLResponse) while the signature verification logic only checks literal parameter names. An attacker can use this discrepancy to provide a crafted, unsigned SAML message that the server processes instead of a legitimately signed one, leading to full account takeover of federated users.
- CVE-2026-96677Critical
Cross-site Scripting (XSS) vulnerability in Apache Juneau. HTML document serialization does not HTML-encode variable substitutions in page chrome fields (header, nav, footer, etc.), so applications that place request-derived values there reflect them unencoded.
- CVE-2026-73117Critical
HTTP Response Splitting (CRLF injection in HTTP headers) vulnerability in Apache Juneau. The REST server passed response header values and redirect targets to the servlet container unchecked, so request-derived data could allow header injection or redirect to an arbitrary site.
- CVE-2026-73116Critical
Insufficiently Protected Credentials vulnerability in Apache Juneau. The RestClient followed HTTP redirects while keeping credential headers from the original request, so a server redirecting to a different host, port, or from HTTPS to HTTP could receive Authorization, Cookie, Proxy-Authorization and X-API-Key headers.
- CVE-2026-73101Critical
Generation of Error Message Containing Sensitive Information vulnerability in Apache Juneau. The REST server sends the internal exception class and message to clients in a "Thrown" response header on every error response and may include internal exception messages in the error body, even with stack-trace rendering disabled.
- CVE-2026-73100Critical
Insertion of Sensitive Information into Log File vulnerability in Apache Juneau. The default REST server call logger records request headers for requests ending in a server error without redaction, so Authorization, Cookie, Proxy-Authorization and X-API-Key headers are written in cleartext to the application log.
- CVE-2026-73099Critical
Cross-Site Request Forgery (CSRF) vulnerability in Apache Juneau. The REST server accepts a "content" query parameter that replaces the request body and is enabled by default on every HTTP method including GET, so a cross-site link can deliver an attacker-chosen request body without a CORS preflight.
- CVE-2026-73098Critical
Improper control of dynamically-loaded code vulnerability in Apache Juneau. When parsing a value into a property of type java.lang.Class, the default class swap loaded the named class with initialization enabled, so input naming a class on the application classpath ran that class's static initializer.
- CVE-2026-121489Critical
Path Traversal vulnerability in Apache Juneau. The microservice DirectoryResource does not keep request paths inside its configured root directory; when an application enables the resource's view, upload or delete settings (all off by default), a client can read, write or delete files outside the root.
- CVE-2026-100109Critical
The Security For WooCommerce WordPress plugin from 1.0.10 to 1.0.16 does not perform capability checks when creating users through an action available to unauthenticated visitors, and lets the caller choose the new account's role. This allows unauthenticated attackers to create administrator accounts and take over the site.
Original NVD description (English source)
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'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'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->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 into a stale writable mapping of the freed DMA buffer pages is available on request.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS