Junglewise Threat Intelligence

CVE-2025-39998: Linux Kernel buffer overflow in SCSI target_core_configfs

CVE-2025-39998 · Severity: high · CVSS 7.1 · Published 2025-10-15

Technologies: Linux Kernel. Vendors: Linux.

Executive brief

A vulnerability was identified in the Linux kernel's SCSI target subsystem, which manages how the system presents storage devices to other computers on a network. A flaw in how the system handles long device or adapter names could allow a local user to trigger a buffer overflow. This could lead to a system crash or potentially allow unauthorized access to sensitive kernel memory, impacting the stability and security of the storage server.

Technical details

A buffer overflow exists in the 'target_lu_gp_members_show' function within 'drivers/target/target_core_configfs.c'. The vulnerability is caused by improper handling of the 'snprintf' return value when formatting HBA and device names into a 256-byte buffer (LU_GROUP_NAME_BUF). Because 'snprintf' returns the length of the string that *would* have been written, a sufficiently long combined string can cause a subsequent 'memcpy' operation to exceed the allocated buffer bounds. A local attacker with low privileges can exploit this to trigger a kernel crash (DoS) or potentially read out-of-bounds kernel memory. The issue has been resolved by adding explicit length checks for 'cur_len' against 'LU_GROUP_NAME_BUF'.

Affected products

  • Linux Linux Kernel 2.6.38 to 6.11.x

Timeline

  • 2025-09-20: disclosed: Vulnerability reported by Wang Haoran
  • 2025-09-29: patched: Initial patch committed to mainline kernel
  • 2025-10-15: advisory: CVE published

References

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