CVE-2025-68366 — nbd: defer config unlock in nbd_genl_connect

Affected: Linux

In the Linux kernel, the following vulnerability has been resolved:

nbd: defer config unlock in nbd_genl_connect

There is one use-after-free warning when running NBD_CMD_CONNECT and NBD_CLEAR_SOCK:

nbd_genl_connect nbd_alloc_and_init_config // config_refs=1 nbd_start_device // config_refs=2 set NBD_RT_HAS_CONFIG_REF open nbd // config_refs=3 recv_work done // config_refs=2 NBD_CLEAR_SOCK // config_refs=1 close nbd // config_refs=0 refcount_inc -> uaf

------------[ cut here ]------------ refcount_t: addition on 0; use-after-free. WARNING: CPU: 24 PID: 1014 at lib/refcount.c:25 refcount_warn_saturate+0x12e/0x290 nbd_genl_connect+0x16d0/0x1ab0 genl_family_rcv_msg_doit+0x1f3/0x310 genl_rcv_msg+0x44a/0x790

The issue can be easily reproduced by adding a small delay before refcount_inc(&nbd->config_refs) in nbd_genl_connect():

mutex_unlock(&nbd->config_lock); if (!ret) { set_bit(NBD_RT_HAS_CONFIG_REF, &config->runtime_flags); + printk("before sleep\n"); + mdelay(5 * 1000); + printk("after sleep\n"); refcount_inc(&nbd->config_refs); nbd_connect_reply(info, nbd->index); }

USN-8094-1 — linux, linux-aws, linux-aws-6.17, linux-gcp, linux-hwe-6.17, linux-oracle, linux-oracle-6.17 vulnerabilities

Affected: Ubuntu:24.04:LTS: linux-aws-6.17, Ubuntu:24.04:LTS: linux-hwe-6.17, Ubuntu:24.04:LTS: linux-oracle-6.17, Ubuntu:25.10: linux, Ubuntu:25.10: linux-aws, Ubuntu:25.10: linux-gcp, Ubuntu:25.10: linux-oracle

Qualys discovered that several vulnerabilities existed in the AppArmor Linux kernel Security Module (LSM). An unprivileged local attacker could use these issues to load, replace, and remove arbitrary AppArmor profiles causing denial of service, exposure of sensitive information (kernel memory), local privilege escalation, or possibly escape a container. (LP: #2143853)

It was discovered that some AMD Zen 5 processors supporting RDSEED instruction did not properly handle entropy, potentially resulting in the consumption of insufficiently random values. A local attacker could possibly use this issue to influence the values returned by the RDSEED instruction causing loss of confidentiality and integrity. (CVE-2025-62626)

Several security issues were discovered in the Linux kernel. An attacker could possibly use these to compromise the system. This update corrects flaws in the following subsystems: - ARM64 architecture; - S390 architecture; - x86 architecture; - Block layer subsystem; - Cryptographic API; - Compute Acceleration Framework; - ATM drivers; - Network block device driver; - Bluetooth drivers; - Data acquisition framework and drivers; - Hardware crypto device drivers; - Device frequency scaling framework; - Intel Stratix 10 firmware drivers; - GPIO subsystem; - GPU drivers; - Microsoft Hyper-V drivers; - CoreSight HW tracing drivers; - IIO subsystem; - InfiniBand drivers; - Input Device core drivers; - Input Device (Tablet) d…

Most recent entries from all

CVE-2025-68366 — nbd: defer config unlock in nbd_genl_connect

USN-8094-1 — linux, linux-aws, linux-aws-6.17, linux-gcp, linux-hwe-6.17, linux-oracle, linux-oracle-6.17 vulnerabilities