PoC Index85,100 CVEs with PoCs

CVE-2019-15794

Reference counting error in overlayfs/shiftfs error path when used in conjuction with aufs

MEDIUM 6.7EPSS 1.2%

Overlayfs in the Linux kernel and shiftfs, a non-upstream patch to the Linux kernel included in the Ubuntu 5.0 and 5.3 kernel series, both replace vma->vm_file in their mmap handlers. On error the original value is not restored, and the reference is put for the file to which vm_file points. On upstream kernels this is not an issue, as no callers dereference vm_file following after call_mmap() returns an error. However, the aufs patchs change mmap_region() to replace the fput() using a local variable with vma_fput(), which will fput() vm_file, leading to a refcount underflow.

Affected
Ubuntu · Linux kernel
CVSS v3.1 NVD
6.7 MEDIUMCVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
CVSS v3.1 UBUNTU
7.1 HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
CVSS v2.0 NVD
7.2 HIGHAV:L/AC:L/Au:N/C:C/I:C/A:C
EPSS
1.16% chance of exploitation in the next 30 days, 67th percentile
Published
2020-04-23
Updated
2024-09-16

ExploitDB entries (1)

Security advisories

References