CVE-2019-5544: VMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Vulnerability
CVSS: 9.8v3.1CriticalKEVRansomwareAnalyzed
AliasesMGASA-2020-0075RHSA-2019:4240RHSA-2020:0199UBUNTU-CVE-2019-5544USN-4919-1
Published 06-12-2019Last modified 21-10-2025
Vulnerability summary
CVE-2019-5544 is a critical (CVSS 9.8) Out-of-bounds Write vulnerability in VMware VMware ESXi and Horizon DaaS. It is known to be exploited: CISA lists it, first on 03-11-2021. It has been used in ransomware campaigns. EPSS estimates a 98.13% chance of exploitation in the next 30 days, higher than 99.9% of scored vulnerabilities.
CVSS score
9.8/10
010
Critical · v3.1 (CVE.org)EPSS score
98.13%
0%100%
Critical · +0.87 pp in 30 daysKEVListedCISA
RansomwareKnown useFlagged by CISA
Public exploits0No public exploits recorded
Advisory lineage
Upstream 0 · Downstream 1Timeline
- 06-12-2019PublishedVulnerability first disclosed.
- 03-11-2021Added to CISA KEVVMware ESXi and Horizon DaaS OpenSLP Heap-Based Buffer Overflow Vulnerability
- 03-05-2022CISA remediation dueApply updates per vendor instructions.
- 21-10-2025Last modifiedVulnerability information updated.
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.
CVSS metrics
5 scores · 4 sources · 3 versionsCritical 9.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 3 agree
- OSV · UbuntuEcosystem advisory · calculated9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- NVDNIST9.8CriticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Critical 9.8Preferred score · OSV · Red hat (Ecosystem advisory) · calculated from vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesSingle source
High 7.5Preferred score · NVD (NIST)
AV:N/AC:L/Au:N/C:P/I:P/A:PSourcesSingle source
EPSS trend
Probability
98.13%
Chance of exploitation in the next 30 days
Percentile
100%
Versus all other CVEs
30-day change
+0.87 pp
From 97.26% on 19-09-2026
19-09-202619-10-2026
EPSS score98.13%
Known exploited
Compare KEV catalogs
CISA KEVListed- Added
- 03-11-2021
- Federal due date
- 03-05-2022
Ransomware
CISA required action
Apply updates per vendor instructions. nvd.nist.gov/vuln/detail/CVE-2019-5544
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Redhat16 products
- enterprise_linux_desktop6.0 | 7.0
- enterprise_linux_for_ibm_z_systems6.0_s390x | 7.0_s390x
- enterprise_linux_for_ibm_z_systems_eus7.7_s390x
- enterprise_linux_for_power_big_endian6.0_ppc64 | 7.0_ppc64
- enterprise_linux_for_power_big_endian_eus7.7_ppc64
Vmware2 products
- esxiEOL6.0 | 6.0:1 | 6.0:1a | 6.0:1b | 6.0:2 | 6.0:3 | 6.0:3a | 6.0:600-201504401 | 6.0:600-201505401 | 6.0:600-201507101 | 6.0:600-201507102 | 6.0:600-201507401 | 6.0:600-201507402 | 6.0:600-201507403 | 6.0:600-201507404 | 6.0:600-201507405 | 6.0:600-201507406 | 6.0:600-201507407 | 6.0:600-201509101 | 6.0:600-201509102 | 6.0:600-201509201 | 6.0:600-201509202 | 6.0:600-201509203 | 6.0:600-201509204 | 6.0:600-201509205 | 6.0:600-201509206 | 6.0:600-201509207 | 6.0:600-201509208 | 6.0:600-201509209 | 6.0:600-201509210 | 6.0:600-201510401 | 6.0:600-201511401 | 6.0:600-201601101 | 6.0:600-201601102 | 6.0:600-201601401 | 6.0:600-201601402 | 6.0:600-201601403 | 6.0:600-201601404 | 6.0:600-201601405 | 6.0:600-201602401 | 6.0:600-201603101 | 6.0:600-201603102 | 6.0:600-201603201 | 6.0:600-201603202 | 6.0:600-201603203 | 6.0:600-201603204 | 6.0:600-201603205 | 6.0:600-201603206 | 6.0:600-201603207 | 6.0:600-201603208 | 6.0:600-201605401 | 6.0:600-201608101 | 6.0:600-201608401 | 6.0:600-201608402 | 6.0:600-201608403 | 6.0:600-201608404 | 6.0:600-201608405 | 6.0:600-201610410 | 6.0:600-201611401 | 6.0:600-201611402 | 6.0:600-201611403 | 6.0:600-201702101 | 6.0:600-201702102 | 6.0:600-201702201 | 6.0:600-201702202 | 6.0:600-201702203 | 6.0:600-201702204 | 6.0:600-201702205 | 6.0:600-201702206 | 6.0:600-201702207 | 6.0:600-201702208 | 6.0:600-201702209 | 6.0:600-201702210 | 6.0:600-201702211 | 6.0:600-201702212 | 6.0:600-201703401 | 6.0:600-201706101 | 6.0:600-201706102 | 6.0:600-201706103 | 6.0:600-201706401 | 6.0:600-201706402 | 6.0:600-201706403 | 6.0:600-201710301 | 6.0:600-201811001 | 6.0:600-201811401 | 6.5 | 6.5:650-201701001 | 6.5:650-201703001 | 6.5:650-201703002 | 6.5:650-201704001 | 6.5:650-201707101 | 6.5:650-201707102 | 6.5:650-201707103 | 6.5:650-201707201 | 6.5:650-201707202 | 6.5:650-201707203 | 6.5:650-201707204 | 6.5:650-201707205 | 6.5:650-201707206 | 6.5:650-201707207 | 6.5:650-201707208 | 6.5:650-201707209 | 6.5:650-201707210 | 6.5:650-201707211 | 6.5:650-201707212 | 6.5:650-201707213 | 6.5:650-201707214 | 6.5:650-201707215 | 6.5:650-201707216 | 6.5:650-201707217 | 6.5:650-201707218 | 6.5:650-201707219 | 6.5:650-201707220 | 6.5:650-201707221 | 6.5:650-201710001 | 6.5:650-201712001 | 6.5:650-201803001 | 6.5:650-201806001 | 6.5:650-201808001 | 6.5:650-201810001 | 6.5:650-201810002 | 6.5:650-201811001 | 6.5:650-201811002 | 6.5:650-201811301 | 6.5:650-201901001 | 6.5:650-201903001 | 6.5:650-201905001 | 6.5:650-201908001 | 6.5:650-201910001 | 6.5:650-20191004001 | 6.5:650-201911001 | 6.5:650-201911401 | 6.5:650-201911402 | 6.7 | 6.7:670-201806001 | 6.7:670-201807001 | 6.7:670-201808001 | 6.7:670-201810001 | 6.7:670-201810101 | 6.7:670-201810102 | 6.7:670-201810103 | 6.7:670-201810201 | 6.7:670-201810202 | 6.7:670-201810203 | 6.7:670-201810204 | 6.7:670-201810205 | 6.7:670-201810206 | 6.7:670-201810207 | 6.7:670-201810208 | 6.7:670-201810209 | 6.7:670-201810210 | 6.7:670-201810211 | 6.7:670-201810212 | 6.7:670-201810213 | 6.7:670-201810214 | 6.7:670-201810215 | 6.7:670-201810216 | 6.7:670-201810217 | 6.7:670-201810218 | 6.7:670-201810219 | 6.7:670-201810220 | 6.7:670-201810221 | 6.7:670-201810222 | 6.7:670-201810223 | 6.7:670-201810224 | 6.7:670-201810225 | 6.7:670-201810226 | 6.7:670-201810227 | 6.7:670-201810228 | 6.7:670-201810229 | 6.7:670-201810230 | 6.7:670-201810231 | 6.7:670-201810232 | 6.7:670-201810233 | 6.7:670-201810234 | 6.7:670-201811001 | 6.7:670-201901001 | 6.7:670-201901401 | 6.7:670-201901402 | 6.7:670-201901403 | 6.7:670-201903001 | 6.7:670-201904001 | 6.7:670-201904201 | 6.7:670-201904202 | 6.7:670-201904203 | 6.7:670-201904204 | 6.7:670-201904205 | 6.7:670-201904206 | 6.7:670-201904207 | 6.7:670-201904208 | 6.7:670-201904209 | 6.7:670-201904210 | 6.7:670-201904211 | 6.7:670-201904212 | 6.7:670-201904213 | 6.7:670-201904214 | 6.7:670-201904215 | 6.7:670-201904216 | 6.7:670-201904217 | 6.7:670-201904218 | 6.7:670-201904219 | 6.7:670-201904220 | 6.7:670-201904221 | 6.7:670-201904222 | 6.7:670-201904223 | 6.7:670-201904224 | 6.7:670-201904225 | 6.7:670-201904226 | 6.7:670-201904227 | 6.7:670-201904228 | 6.7:670-201904229 | 6.7:670-201905001 | 6.7:670-201906002 | 6.7:670-201908101 | 6.7:670-201908102 | 6.7:670-201908103 | 6.7:670-201908104 | 6.7:670-201908201 | 6.7:670-201908202 | 6.7:670-201908203 | 6.7:670-201908204 | 6.7:670-201908205 | 6.7:670-201908206 | 6.7:670-201908207 | 6.7:670-201908208 | 6.7:670-201908209 | 6.7:670-201908210 | 6.7:670-201908211 | 6.7:670-201908212 | 6.7:670-201908213 | 6.7:670-201908214 | 6.7:670-201908215 | 6.7:670-201908216 | 6.7:670-201908217 | 6.7:670-201908218 | 6.7:670-201908219 | 6.7:670-201908220 | 6.7:670-201908221 | 6.7:670-201911001
- horizon_daas≥ 8.0.0, < 9.0.0.0
Fedoraproject1 product
- fedoraEOL30 | 31
Mageia1 product
- openslp< 2.0.0-10.1.mga7
Openslp1 product
- openslp≤ 2.0.0
Ubuntu1 product
- openslp-dfsg< 1.2.1-9ubuntu0.3+esm1 | < 1.2.1-11ubuntu0.16.04.2
6 vendors · 22 products
References
23 links- access.redhat.com/errata/RHSA-2019:4240Vendor AdvisoryX Refsource REDHATAdvisoryThird Party Advisory
- access.redhat.com/errata/RHSA-2020:0199Vendor AdvisoryX Refsource REDHATAdvisoryThird Party Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-5544Government ResourceUS Government Resource
