CVE-2019-5544

VMware ESXi and Horizon DaaS: OpenSLP Heap-Based Buffer Overflow

As of , CVE-2019-5544 in VMware ESXi and Horizon DaaS is on CISA's list of exploited vulnerabilities: CISA listed it on . Our patch-first group: Patch this week.

Exploited
Yes: CISA listed it on 3 November 2021
US federal deadline
3 May 2022181 days after CISA listed it. US federal civilian agencies must fix it by then.
Used in ransomware campaigns
Known
EPSS score
0.97Higher than 99% of the CVEs EPSS scores. EPSS estimates the chance of exploitation activity in the next 30 days.
EPSS when listed
Not availableCISA listed it before 4 February 2022, where the EPSS files we read begin.
Public exploit
None foundNeither Metasploit nor Exploit-DB lists one.
Fix
No vendor link in CISA's entry

What CISA says to do

Apply updates per vendor instructions.

CISA's required action

What the flaw is

VMware ESXi and Horizon Desktop as a Service (DaaS) OpenSLP contains a heap-based buffer overflow vulnerability that allows an attacker with network access to port 427 to overwrite the heap of the OpenSLP service to perform remote code execution.

CISA's description

OpenSLP as used in ESXi and the Horizon DaaS appliances has a heap overwrite issue. VMware has evaluated the severity of this issue to be in the Critical severity range with a maximum CVSSv3 base score of 9.8.

The CVE record's description, from vmware

CVE published
6 December 2019
Assigned by
vmware
CVSS
9.8 Critical (CVSS 3.1, from CISA-ADP)
CWE-787
Out-of-bounds Write
CISA SSVC, exploitation
active
CISA SSVC, automatable
yes
CISA SSVC, technical impact
total

Timeline

  1. The CVE record was published.
  2. CISA added it to its list of exploited vulnerabilities.
  3. The US federal deadline to fix it.

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