CVE-2019-11487 - Use After Free

Severity

72%

Complexity

39%

Confidentiality

165%

The Linux kernel before 5.1-rc5 allows page->_refcount reference count overflow, with resultant use-after-free issues, if about 140 GiB of RAM exists. This is related to fs/fuse/dev.c, fs/pipe.c, fs/splice.c, include/linux/mm.h, include/linux/pipe_fs_i.h, kernel/trace/trace.c, mm/gup.c, and mm/hugetlb.c. It can occur with FUSE requests.

The Linux kernel before 5.1-rc5 allows page->_refcount reference count overflow, with resultant use-after-free issues, if about 140 GiB of RAM exists. This is related to fs/fuse/dev.c, fs/pipe.c, fs/splice.c, include/linux/mm.h, include/linux/pipe_fs_i.h, kernel/trace/trace.c, mm/gup.c, and mm/hugetlb.c. It can occur with FUSE requests.

CVSS 3.0 Base Score 7.8. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H).

CVSS 2.0 Base Score 7.2. CVSS Attack Vector: local. CVSS Attack Complexity: low. CVSS Vector: (AV:L/AC:L/Au:N/C:C/I:C/A:C).

Demo Examples

Use After Free

CWE-416

The following example demonstrates the weakness.


               
}
free(buf3R2);

Use After Free

CWE-416

The following code illustrates a use after free error:


               
}
free(ptr);
logError("operation aborted before commit", ptr);

When an error occurs, the pointer is immediately freed. However, this pointer is later incorrectly used in the logError function.

Overview

First reported 5 years ago

2019-04-23 22:29:00

Last updated 5 years ago

2019-05-17 10:29:00

Affected Software

Linux Kernel

Linux Linux Kernel 5.1 Release Candidate 1

5.1

Linux Linux Kernel 5.1 Release Candidate 2

5.1

Linux Linux Kernel 5.1 Release Candidate 3

5.1

Linux Linux Kernel 5.1 Release Candidate 4

5.1

References

openSUSE-SU-2019:1570

openSUSE-SU-2019:1571

openSUSE-SU-2019:1579

[oss-security] 20190429 Linux kernel: multiple issues

Third Party Advisory

108054

Third Party Advisory

RHSA-2019:2703

RHSA-2019:2741

RHSA-2020:0174

https://bugs.chromium.org/p/project-zero/issues/detail?id=1752

Exploit, Mitigation, Third Party Advisory

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=15fab63e1e57be9fdb5eec1bbc5916e9825e9acb

Patch, Vendor Advisory

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=6b3a707736301c2128ca85ce85fb13f60b5e350a

Patch, Vendor Advisory

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=88b1a17dfc3ed7728316478fae0f5ad508f50397

Patch, Vendor Advisory

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=8fde12ca79aff9b5ba951fce1a2641901b8d8e64

Patch, Vendor Advisory

https://git.kernel.org/cgit/linux/kernel/git/torvalds/linux.git/commit/?id=f958d7b528b1b40c44cfda5eabe2d82760d868c3

Patch, Vendor Advisory

https://github.com/torvalds/linux/commit/15fab63e1e57be9fdb5eec1bbc5916e9825e9acb

Patch, Third Party Advisory

https://github.com/torvalds/linux/commit/6b3a707736301c2128ca85ce85fb13f60b5e350a

Patch, Third Party Advisory

https://github.com/torvalds/linux/commit/88b1a17dfc3ed7728316478fae0f5ad508f50397

Patch, Third Party Advisory

https://github.com/torvalds/linux/commit/8fde12ca79aff9b5ba951fce1a2641901b8d8e64

Patch, Third Party Advisory

https://github.com/torvalds/linux/commit/f958d7b528b1b40c44cfda5eabe2d82760d868c3

Patch, Third Party Advisory

[debian-lts-announce] 20190914 [SECURITY] [DLA 1919-1] linux-4.9 security update

[debian-lts-announce] 20190915 [SECURITY] [DLA 1919-2] linux-4.9 security update

https://lwn.net/Articles/786044/

Exploit, Third Party Advisory

https://security.netapp.com/advisory/ntap-20190517-0005/

https://support.f5.com/csp/article/K14255532

USN-4069-1

USN-4069-2

USN-4115-1

USN-4118-1

USN-4145-1

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