Use After Free Affecting torvalds/linux package, versions [,4.9.190)[4.14.0,4.14.139)


Severity

Recommended
0.0
high
0
10

CVSS assessment made by Snyk's Security Team. Learn more

Threat Intelligence

EPSS
0.03% (7th percentile)

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  • Snyk IDSNYK-UNMANAGED-TORVALDSLINUX-3005591
  • published26 Jan 2022
  • disclosed20 Aug 2019
  • creditUnknown

Introduced: 20 Aug 2019

CVE-2019-15239  (opens in a new tab)
CWE-416  (opens in a new tab)

How to fix?

Upgrade torvalds/linux to version 4.9.190, 4.14.139 or higher.

Overview

Affected versions of this package are vulnerable to Use After Free. In the Linux kernel, a certain net/ipv4/tcp_output.c change, which was properly incorporated into 4.16.12, was incorrectly backported to the earlier longterm kernels, introducing a new vulnerability that was potentially more severe than the issue that was intended to be fixed by backporting. Specifically, by adding to a write queue between disconnection and re-connection, a local attacker can trigger multiple use-after-free conditions. This can result in a kernel crash, or potentially in privilege escalation. NOTE: this affects (for example) Linux distributions that use 4.9.x longterm kernels before 4.9.190 or 4.14.x longterm kernels before 4.14.139.

CVSS Base Scores

version 3.1