An issue was discovered in disable_priv_mode in shell.c in GNU Bash through 5.0 patch 11. By default, if Bash is run with its effective UID not equal to its real UID, it will drop privileges by setting its effective UID to its real UID. However, it does so incorrectly. On Linux and other systems that support "saved UID" functionality, the saved UID is not dropped. An attacker with command execution in the shell can use "enable -f" for runtime loading of a new builtin, which can be a shared object that calls setuid() and therefore regains privileges. However, binaries running with an effective UID of 0 are unaffected.
Se descubrió un problema en la función disable_priv_mode en el archivo shell.c en GNU Bash versiones hasta la versión 5.0 parche 11. Por defecto, si Bash es ejecutado con su UID efectivo no igual a su UID real, perderá privilegios al establecer su UID efectivo en su UID real. Sin embargo, lo hace incorrectamente. En Linux y otros sistemas que admiten la funcionalidad "saved UID", el UID guardado no se descarta. Un atacante con ejecución de comando en el shell puede utilizar "enable -f" para la carga del tiempo de ejecución un nuevo builtin, que puede ser un objeto compartido que llama a setuid() y, por lo tanto, recupera privilegios. Sin embargo, los archivos binarios que son ejecutados con un UID efectivo de 0 no están afectados.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
| Attack Vector | LOCAL |
|---|---|
| Attack Complexity | LOW |
| Privileges Required | LOW |
| User Interaction | NONE |
| Scope | UNCHANGED |
| Confidentiality Impact | HIGH |
| Integrity Impact | HIGH |
| Availability Impact | HIGH |
AV:L/AC:L/Au:N/C:C/I:C/A:C
| Access Vector | LOCAL |
|---|---|
| Access Complexity | LOW |
| Authentication | NONE |
| Confidentiality Impact | COMPLETE |
| Integrity Impact | COMPLETE |
| Availability Impact | COMPLETE |
| Source | Type | Description |
|---|---|---|
| [email protected] | Primary |
en
CWE-273
|
| 134c704f-9b21-4f2e-91b3-4a467353bcc0 | Secondary |
en
CWE-273
|
| Vendor | Product | Version | Update | Type |
|---|---|---|---|---|
| gnu | bash | * | <built-in method update of dict object at 0x7fd370344040> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd369b55700> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd3703446c0> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd36b3f8ac0> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd370344b00> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd370346780> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd340bfe3c0> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd369b57bc0> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd369b55c00> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd370344640> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd340bfecc0> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd369b55100> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd340bfdd80> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd369b55f00> | Application |
| gnu | bash | 5.0 | <built-in method update of dict object at 0x7fd38674cb40> | Application |
| netapp | hci_management_node | - | <built-in method update of dict object at 0x7fd340bfcd40> | Application |
| netapp | oncommand_unified_manager | * | <built-in method update of dict object at 0x7fd369b54dc0> | Application |
| netapp | solidfire | - | <built-in method update of dict object at 0x7fd3703452c0> | Application |
| oracle | communications_cloud_native_core_policy | 1.14.0 | <built-in method update of dict object at 0x7fd369b55140> | Application |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:a:gnu:bash:*:*:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:beta1:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:beta2:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch1:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch10:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch11:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch2:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch3:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch4:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch5:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch6:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch7:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch8:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:patch9:*:*:*:*:*:* |
| Yes | cpe:2.3:a:gnu:bash:5.0:rc1:*:*:*:*:*:* |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:a:netapp:hci_management_node:-:*:*:*:*:*:*:* |
| Yes | cpe:2.3:a:netapp:oncommand_unified_manager:*:*:*:*:*:vmware_vsphere:*:* |
| Yes | cpe:2.3:a:netapp:solidfire:-:*:*:*:*:*:*:* |
| Vulnerable | CPE |
|---|---|
| Yes | cpe:2.3:a:oracle:communications_cloud_native_core_policy:1.14.0:*:*:*:*:*:*:* |