SB2018071046 - Fedora 28 update for kernel



SB2018071046 - Fedora 28 update for kernel

Published: July 10, 2018 Updated: April 24, 2025

Security Bulletin ID SB2018071046
Severity
Low
Patch available
YES
Number of vulnerabilities 7
Exploitation vector Local access
Highest impact Denial of service

Breakdown by Severity

Low 100%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 7 secuirty vulnerabilities.


1) Integer overflow (CVE-ID: CVE-2018-13053)

The vulnerability allows a local user to escalate privileges on the system.

The vulnerability exists in kernel/time/alarmtimer.c within the alarm_timer_nsleep function. A local user can trigger integer overflow due to ktime_add_safe is not used and escalate privileges on the system.


2) Integer overflow (CVE-ID: CVE-2018-12896)

The vulnerability allows a local user to perform a denial of service (DoS) attack.

An issue was discovered in the Linux kernel through 4.17.3. An Integer Overflow in kernel/time/posix-timers.c in the POSIX timer code is caused by the way the overrun accounting works. Depending on interval and expiry time values, the overrun can be larger than INT_MAX, but the accounting is int based. This basically makes the accounting values, which are visible to user space via timer_getoverrun(2) and siginfo::si_overrun, random. For example, a local user can cause a denial of service (signed integer overflow) via crafted mmap, futex, timer_create, and timer_settime system calls.


3) Null pointer dereference (CVE-ID: CVE-2018-13093)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The vulnerability exists in the lookup_slow() function in the Extended File System (XFS) component, as defined in the source code file fs/xfs/xfs_icache.c due to boundary error when mounting XFS filesystems. A local attacker can mount an XFS filesystem that submits malicious input, trigger NULL pointer dereference memory error and cause the affected software to terminate abnormally.


4) Null pointer dereference (CVE-ID: CVE-2018-13094)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The vulnerability exists due to NULL pointer dereference in the fs/xfs/libxfs/xfs_attr_leaf.c source code file in the Extended File System (XFS) component when the xfs_da_shrink_inode() function is called with a NULL byte pointer. A local attacker can mount and perform operations on a crafted XFS image, trigger a NULL pointer dereference condition in the xfs_trans_binval() function and cause the service to crash.


5) Null pointer dereference (CVE-ID: CVE-2018-13095)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The vulnerability exists in the xfs_bmap_extents_to_btree() function in the Extended File System (XFS) component, as defined in the source code file fs/xfs/libxfs/xfs_inode_buf.c due to boundary error when mounting XFS filesystems. A local attacker can access the system, mount an XFS filesystem that submits malicious input, trigger a NULL pointer dereference memory error and cause the affected software to terminate abnormally.


6) Security restrictions bypass (CVE-ID: CVE-2018-13405)

The vulnerability allows a local attacker to create arbitrary files on the target system.

The vulnerability exists due to the inode_init_owner function, as defined in the fs/inode.c source code file, allows the creation of arbitrary files in set-group identification (SGID) directories. A local attacker can create arbitrary files with unintended group ownership.


7) Integer overflow (CVE-ID: CVE-2018-13406)

The vulnerability allows a local attacker to cause DoS condition on the target system.

The vulnerability exists due to integer overflow in the uvesafb_setcmap function, as defined in the drivers/video/fbdev/uvesafb.c source code file. A local attacker can execute a file or program that submits malicious input, trigger memory corruption and cause the affected software to crash.


Remediation

Install update from vendor's website.