CVE-2026-74709
xsk: clear metadata pointer when no timestamp is requested
Description
In the Linux kernel, the following vulnerability has been resolved: xsk: clear metadata pointer when no timestamp is requested User space can change metadata flags after request processing. Rereading them during completion can therefore make the kernel write a timestamp that was not requested when the packet was submitted. Clear the metadata pointer during request processing unless timestamp completion is requested. Completion handling can then use the pointer itself instead of rereading the flags. On the mlx5 multi-packet WQE path metadata is evaluated per batch: xsk_tx_metadata_request() runs only for the descriptor that starts a session, just like the checksum offload that is applied once through the shared WQE. Only that descriptor's pointer is reset, so completion handling can record a timestamp for the other descriptors of the session regardless of their own XDP_TXMD_FLAGS_TIMESTAMP bit. The write stays inside the metadata area; the single-WQE, other zero-copy, and generic paths reset the pointer per descriptor and are unaffected.
INFO
Published Date :
Aug. 22, 2026, 4:16 p.m.
Last Modified :
Oct. 14, 2026, 1:10 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Solution
- Apply the Linux kernel update.
- Verify timestamp handling after update.
- Test packet submission and completion.
- Ensure metadata flags are correctly processed.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-74709.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-74709 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-74709
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-74709 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-74709 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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CVE Translated by [email protected]
Oct. 14, 2026
Action Type Old Value New Value Added Translation Title: Linux, Description: En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: xsk: borrar el puntero de metadatos cuando no se solicita una marca de tiempo El espacio de usuario puede cambiar los indicadores de metadatos después del procesamiento de la solicitud. Volver a leerlos durante la finalización puede, por lo tanto, hacer que el kernel escriba una marca de tiempo que no fue solicitada cuando el paquete fue enviado. Borrar el puntero de metadatos durante el procesamiento de la solicitud a menos que se solicite la finalización de la marca de tiempo. El manejo de la finalización puede entonces usar el propio puntero en lugar de volver a leer los indicadores. En la ruta WQE de múltiples paquetes mlx5, los metadatos son evaluados por lote: xsk_tx_metadata_request() se ejecuta solo para el descriptor que inicia una sesión, al igual que la descarga de suma de verificación que se aplica una vez a través del WQE compartido. Solo el puntero de ese descriptor se restablece, por lo que el manejo de la finalización puede registrar una marca de tiempo para los otros descriptores de la sesión independientemente de su propio bit XDP_TXMD_FLAGS_TIMESTAMP. La escritura permanece dentro del área de metadatos; las rutas de WQE único, otras de copia cero y genéricas restablecen el puntero por descriptor y no se ven afectadas. -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Aug. 22, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': 'ca4419f15abd19ba8be1e109661b60f9f5b6c9f0', 'lessThan': '0ba2e1eb07a826d021344e2f146b6716c58139eb', 'versionType': 'git'}, {'status': 'affected', 'version': 'ca4419f15abd19ba8be1e109661b60f9f5b6c9f0', 'lessThan': 'eb4c613d4ebc3f664e70d572b8867ba114a8754e', 'versionType': 'git'}, {'status': 'affected', 'version': 'ca4419f15abd19ba8be1e109661b60f9f5b6c9f0', 'lessThan': '9f60a67df8d3c862503bee62bada8e7089cba438', 'versionType': 'git'}, {'status': 'affected', 'version': 'd9d736c416c9a85f84e15435ba82a177262e745b', 'versionType': 'git'}, {'status': 'affected', 'version': '6.14.2', 'lessThan': '6.15', 'versionType': 'semver'}], 'programFiles': ['include/net/xdp_sock.h', 'net/xdp/xsk.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '6.15'}, {'status': 'unaffected', 'version': '0', 'lessThan': '6.15', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.45', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.1.9', 'versionType': 'semver', 'lessThanOrEqual': '7.1.*'}, {'status': 'unaffected', 'version': '7.2', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['include/net/xdp_sock.h', 'net/xdp/xsk.c'], 'defaultStatus': 'affected'}] Added Description In the Linux kernel, the following vulnerability has been resolved: xsk: clear metadata pointer when no timestamp is requested User space can change metadata flags after request processing. Rereading them during completion can therefore make the kernel write a timestamp that was not requested when the packet was submitted. Clear the metadata pointer during request processing unless timestamp completion is requested. Completion handling can then use the pointer itself instead of rereading the flags. On the mlx5 multi-packet WQE path metadata is evaluated per batch: xsk_tx_metadata_request() runs only for the descriptor that starts a session, just like the checksum offload that is applied once through the shared WQE. Only that descriptor's pointer is reset, so completion handling can record a timestamp for the other descriptors of the session regardless of their own XDP_TXMD_FLAGS_TIMESTAMP bit. The write stays inside the metadata area; the single-WQE, other zero-copy, and generic paths reset the pointer per descriptor and are unaffected. Added Reference https://git.kernel.org/stable/c/0ba2e1eb07a826d021344e2f146b6716c58139eb Added Reference https://git.kernel.org/stable/c/9f60a67df8d3c862503bee62bada8e7089cba438 Added Reference https://git.kernel.org/stable/c/eb4c613d4ebc3f664e70d572b8867ba114a8754e