CVE-2026-90049
net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy()
Description
In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy() skb_zerocopy() copies frags from @from into @to. On an skb_orphan_frags() failure it calls skb_tx_error(@from), a destructive operation on the source skb the copy helper does not own. That completes @from's zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, including the SKBFL_SHARED_FRAG page-ownership marker. Both callers already report the failure on their own drop path. nfnetlink_queue does it at nla_put_failure, and Open vSwitch does it in the flow-miss drop arm of ovs_dp_process_packet(), so nothing is lost by dropping it here. On Open vSwitch's OVS_ACTION_ATTR_USERSPACE path the skb is not freed on this error: do_execute_actions() ignores output_userspace()'s return value and, unless the upcall was the last action, keeps forwarding the same skb through the flow's remaining actions. The uarg is completed while that skb is still in flight, telling the producer its buffers are free, and SKBFL_SHARED_FRAG is cleared on an skb the rest of the stack still handles. That flag is what makes esp_input() call skb_cow_data() instead of decrypting in place, so a later local ESP delivery can decrypt over frags the skb does not own privately. Leave error reporting to the callers.
INFO
Published Date :
Sept. 16, 2026, 11:17 a.m.
Last Modified :
Oct. 19, 2026, 9:18 a.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | CRITICAL | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Update the Linux kernel.
- Review related network component configurations.
- Test the system after the update.
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-2026-90049.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-90049 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-2026-90049
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-2026-90049 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-90049 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 Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Oct. 19, 2026
Action Type Old Value New Value Added Affected Affected value modified. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/90xxx/CVE-2026-90049.json">CVE-2026-90049</a> -
CVE Translated by [email protected]
Sep. 28, 2026
Action Type Old Value New Value Added Translation Title: la biblioteca CGM_NIST_Loader.dll en JT2Go, Teamcenter Visualization, Description: En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta: net: skbuff: no llamar a skb_tx_error() al skb de origen en skb_zerocopy() skb_zerocopy() copia fragmentos de @from a @to. En caso de fallo de skb_orphan_frags(), llama a skb_tx_error(@from), una operación destructiva en el skb de origen que el ayudante de copia no posee. Eso completa el uarg de zerocopy de @from y borra SKBFL_ALL_ZEROCOPY, incluyendo el marcador de propiedad de página SKBFL_SHARED_FRAG. Ambos llamadores ya informan del fallo en su propia ruta de descarte. nfnetlink_queue lo hace en nla_put_failure, y Open vSwitch lo hace en el brazo de descarte por fallo de flujo de ovs_dp_process_packet(), por lo que no se pierde nada al descartarlo aquí. En la ruta OVS_ACTION_ATTR_USERSPACE de Open vSwitch, el skb no se libera en este error: do_execute_actions() ignora el valor de retorno de output_userspace() y, a menos que la llamada ascendente fuera la última acción, sigue reenviando el mismo skb a través de las acciones restantes del flujo. El uarg se completa mientras ese skb todavía está en tránsito, indicando al productor que sus búferes están libres, y SKBFL_SHARED_FRAG se borra en un skb que el resto de la pila aún maneja. Esa bandera es lo que hace que esp_input() llame a skb_cow_data() en lugar de descifrar in situ, para que una entrega ESP local posterior pueda descifrar sobre fragmentos que el skb no posee de forma privada. Dejar el informe de errores a los llamadores. -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 16, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Sep. 16, 2026
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: net: skbuff: don't skb_tx_error() the source skb in skb_zerocopy() skb_zerocopy() copies frags from @from into @to. On an skb_orphan_frags() failure it calls skb_tx_error(@from), a destructive operation on the source skb the copy helper does not own. That completes @from's zerocopy uarg and clears SKBFL_ALL_ZEROCOPY, including the SKBFL_SHARED_FRAG page-ownership marker. Both callers already report the failure on their own drop path. nfnetlink_queue does it at nla_put_failure, and Open vSwitch does it in the flow-miss drop arm of ovs_dp_process_packet(), so nothing is lost by dropping it here. On Open vSwitch's OVS_ACTION_ATTR_USERSPACE path the skb is not freed on this error: do_execute_actions() ignores output_userspace()'s return value and, unless the upcall was the last action, keeps forwarding the same skb through the flow's remaining actions. The uarg is completed while that skb is still in flight, telling the producer its buffers are free, and SKBFL_SHARED_FRAG is cleared on an skb the rest of the stack still handles. That flag is what makes esp_input() call skb_cow_data() instead of decrypting in place, so a later local ESP delivery can decrypt over frags the skb does not own privately. Leave error reporting to the callers. Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/90xxx/CVE-2026-90049.json">CVE-2026-90049</a> Added Reference https://git.kernel.org/stable/c/04dd250a78e268af3e7124beb1dc10ec1dd88d60 Added Reference https://git.kernel.org/stable/c/767ec2a65cc022d303b0c9c12811e7db22057341 Added Reference https://git.kernel.org/stable/c/8069643ae64dfdf634b6c78c7f622e5323031436 Added Reference https://git.kernel.org/stable/c/849bdb83123760a865bcb2970127f4c0b9423ba3 Added Reference https://git.kernel.org/stable/c/8ece906150128d5ec2462aabcc978c568433eca4 Added Reference https://git.kernel.org/stable/c/a13b1e80e5015cd732440b475c0ef443dc4a2157 Added Reference https://git.kernel.org/stable/c/bab5a851e44a3601d31f2aa8043f385bb50ac5d9 Added Reference https://git.kernel.org/stable/c/fb10e0e9b220a2eed08931a60dbaad9a2370c908