CyberSecBulletin
CVE-2019-13272Exploited in the wildNVD status: Analyzed

Linux Kernel Improper Privilege Management

Published Updated By the CyberSecBulletin desk

CVE-2019-13272 is a high-severity vulnerability in Linux Kernel from Linux, with a CVSS 3.1 base score of 7.8 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists versions 3.16.71, 4.2, 4.4.185 as the first without the flaw, so updating Linux Kernel to one of those releases or later removes the exposure. CISA added it to the Known Exploited Vulnerabilities catalogue on December 10, 2021, which means attacks have been observed in the wild.

Patch now

Attackers are already exploiting this vulnerability, according to CISA.

What to do

  1. Update Linux Kernel to 3.16.71 or 4.2 or 4.4.185 or 4.9, whichever matches your release line, or a later version.
  2. CISA's required action: Apply updates per vendor instructions.
  3. Read the advisory on packetstormsecurity.com for workarounds and exact fixed builds.

Affected products and versions

VendorProductAffected versionsFixed in
LinuxLinux Kernel3.16.52 up to, but not including, 3.16.71; 4.1.39 up to, but not including, 4.2; 4.4.40 up to, but not including, 4.4.185; 4.8.16 up to, but not including, 4.9; 4.9.1 up to, but not including, 4.9.185; 4.10 up to, but not including, 4.14.133; 4.15 up to, but not including, 4.19.58; 4.20 up to, but not including, 5.1.173.16.71, 4.2, 4.4.185, 4.9, 4.9.185, 4.14.133
DebianDebian Linux8.0; 9.0; 10.0Not stated
Fedora ProjectFedora29Not stated
CanonicalUbuntu Linux16.04; 18.04; 19.04Not stated
Red HatEnterprise Linux7.0; 8.0Not stated
Red HatEnterprise Linux For Arm 647.0_aarch64Not stated
Red HatEnterprise Linux For IBM Z Systems7.0_s390xNot stated
Red HatEnterprise Linux For Real Time8Not stated
Red HatEnterprise Linux For Real Time For Nfv8.0Not stated
Red HatEnterprise Linux For Real Time For Nfv TUS8.2; 8.4; 8.6; 8.8Not stated
Red HatEnterprise Linux For Real Time TUS8.2; 8.4; 8.6; 8.8Not stated
NetAppAff A700s FirmwareNot specified in the recordNot stated
NetAppH410c FirmwareNot specified in the recordNot stated
NetAppH610s FirmwareNot specified in the recordNot stated
NetAppActive Iq Unified ManagerNot specified in the recordNot stated
NetAppE-series Performance AnalyzerNot specified in the recordNot stated
NetAppE-series Santricity OS Controller11.0.0 through 11.60.3Not stated
NetAppHci Management NodeNot specified in the recordNot stated
NetAppService ProcessorNot specified in the recordNot stated
NetAppSolidfireNot specified in the recordNot stated
NetAppSteelstore Cloud Integrated StorageNot specified in the recordNot stated
NetAppHci Compute NodeNot specified in the recordNot stated

Version data comes from NVD's product matching. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
LocalThe attacker needs local access or must trick a user into running something.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
LowA basic user account is enough.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
HighData or code can be modified at will.
Availability
HighThe component can be taken down completely.

Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.8HighNVD
CVSS 3.17.8HighCISA (ADP)
CVSS 2.07.2HighNVD

Official description

In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

Timeline

  1. CVE record published.
  2. Added to CISA's Known Exploited Vulnerabilities catalogue.
  3. Deadline for US federal agencies to remediate, set by CISA.
  4. CISA published its SSVC assessment (exploitation: active, automatable: no, technical impact: total).
  5. Record last changed materially (score, affected products, status or references).

References

Third-party and government advisories

Other vulnerabilities in Linux Kernel

All Linux Kernel vulnerabilities

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