CVE-2021-2016
published 2021-01-20CVE-2021-2016: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 and prior. Easily…
PriorityP422medium4.9CVSS 3.1
AVNACLPRHUINSUCNINAH
EPSS
2.15%
80.0th percentile
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 and prior. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
Affected
5 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | mysql-8.0 | — | — |
| fedoraproject | fedora | — | — |
| fedoraproject | fedora | — | — |
| oracle | mysql | 8.0.0 – 8.0.19 | — |
| oracle_corporation | mysql_server | — | — |
CVSS provenance
nvdv3.14.9MEDIUMCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
nvdv2.06.8MEDIUMAV:N/AC:L/Au:S/C:N/I:N/A:C
osv4.9MEDIUM
vendor_debian4.9LOW
vendor_oracle4.9MEDIUM
vendor_redhat4.9MEDIUM
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Red Hat
mysql: Server: Optimizer unspecified vulnerability (CPU Jan 2021)
vendor_redhat·2021-01-19·CVSS 4.9
CVE-2021-2016 [MEDIUM] mysql: Server: Optimizer unspecified vulnerability (CPU Jan 2021)
mysql: Server: Optimizer unspecified vulnerability (CPU Jan 2021)
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 and prior. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
Package: mysql (Red Hat Enterprise Linux 6) - Not affected
Package: mariadb (Red Hat Enterprise Linux 7) - Not affected
Package: mariadb:10.3/mariadb (Red Hat Enterprise Linux 8) -
Oracle
Oracle Oracle MySQL Risk Matrix: Server: Optimizer — CVE-2021-2016
vendor_oracle·2021-01-15·CVSS 4.9
CVE-2021-2016 [MEDIUM] Oracle Oracle MySQL Risk Matrix: Server: Optimizer — CVE-2021-2016
Oracle Oracle MySQL Risk Matrix: Server: Optimizer vulnerability
CVE: CVE-2021-2016
CVSS: 4.9
Protocol: MySQL Protocol
Remote exploit: No
Affected versions: Network
Advisory: cpujan2021 (JAN 2021)
Debian
CVE-2021-2016: mysql-8.0 - Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Op...
vendor_debian·2021·CVSS 4.9
CVE-2021-2016 [MEDIUM] CVE-2021-2016: mysql-8.0 - Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Op...
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 and prior. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
Scope: local
sid: resolved
GHSA
GHSA-c34q-4vv7-8478: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
ghsa_unreviewed·2022-05-24
CVE-2021-2016 [MEDIUM] GHSA-c34q-4vv7-8478: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 and prior. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
OSV
CVE-2021-2016: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
osv·2021-01-20·CVSS 4.9
CVE-2021-2016 [MEDIUM] CVE-2021-2016: Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer)
Vulnerability in the MySQL Server product of Oracle MySQL (component: Server: Optimizer). Supported versions that are affected are 8.0.19 and prior. Easily exploitable vulnerability allows high privileged attacker with network access via multiple protocols to compromise MySQL Server. Successful attacks of this vulnerability can result in unauthorized ability to cause a hang or frequently repeatable crash (complete DOS) of MySQL Server. CVSS 3.1 Base Score 4.9 (Availability impacts). CVSS Vector: (CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H).
Elastic
Microsoft Exchange Server UM Spawning Suspicious Processes
elastic_rules·CVSS 7.8
CVE-2021-26857 [HIGH] Microsoft Exchange Server UM Spawning Suspicious Processes
Microsoft Exchange Server UM Spawning Suspicious Processes
Identifies suspicious processes being spawned by the Microsoft Exchange Server Unified Messaging (UM) service. This
activity has been observed exploiting CVE-2021-26857.
Query:
process where host.os.type == "windows" and event.type == "start" and
process.parent.name : ("UMService.exe", "UMWorkerProcess.exe") and
not process.executable : (
"?:\\Windows\\System32\\werfault.exe",
"?:\\Windows\\System32\\wermgr.exe",
"?:\\Program Files\\Microsoft\\Exchange Server\\V??\\Bin\\UMWorkerProcess.exe",
"?:\\Program Files\\Microsoft\\Exchange Server\\Bin\\UMWorkerProcess.exe",
"D:\\Exchange 2016\\Bin\\UMWorkerProcess.exe",
"E:\\ExchangeServer\\Bin\\UMWorkerProcess.exe",
"D:\\Exchange\\Bin\\UMWorkerProcess.exe",
"D:\\Exchange Server\\Bin\\UM
YARA
Linux_Exploit_CVE_2016_5195_364f3b7b
yara·CVSS 7.0
CVE-2016-5195 [HIGH] Linux_Exploit_CVE_2016_5195_364f3b7b
rule Linux_Exploit_CVE_2016_5195_364f3b7b {
meta:
author = "Elastic Security"
id = "364f3b7b-4361-44ca-bf49-e26c123ae4bd"
fingerprint = "ec6cf1d090cd57434c4d3c1c3511fd4b683ff109bfd0ce859552d58cbb83984a"
creation_date = "2021-01-12"
last_modified = "2021-09-16"
threat_name = "Linux.Exploit.CVE-2016-5195"
reference_sample = "0d4c43bf0cdd6486a4bcab988517e58b8c15d276f41600e596ecc28b0b728e69"
severity = 100
arch_context = "x86"
scan_context = "file, memory"
license = "Elastic License v2"
os = "linux"
strings:
$a = { 9C 01 7E 24 48 8B 45 90 48 8B 40 08 48 89 45 F8 48 8B 45 F8 48 }
condition:
all of them
}
No public exploits indexed.
Checkpoint
31st October – Threat Intelligence Report
blogs_checkpoint·2022-10-31
CVE-2022-3723 31st October – Threat Intelligence Report
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## 31st October – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 31st October, please download our Threat Intelligence Bulletin .
Top Attacks and Breaches
US-based communications company Twilio has disclosed a new data breach that occurred on June 2022 allegedly by the same threat actors behind the August hack. The hackers have used voice phishing to trick a Twilio employee into handling over their credentials, which the hackers then used to access customer information.
Cu
Checkpoint
10th October – Threat Intelligence Report
blogs_checkpoint·2022-10-10
CVE-2022-41352 10th October – Threat Intelligence Report
Latest Publications
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Threat Intelligence & Research
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2016
## 10th October – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 10th October, please download our Threat Intelligence Bulletin .
Top Attacks and Breaches
CommonSpirit Health, the second-largest nonprofit hospital chain in the U.S with 140 hospitals and over 1,000 facilities in 21 states, suffered a cybersecurity incident that disrupted medical services across the country. Facilities in Iowa, Nebraska, Tennessee and Washington were among those affected. The nature of the at
Checkpoint
28th June – Threat Intelligence Report
blogs_checkpoint·2021-06-28
CVE-2021-21998 28th June – Threat Intelligence Report
Latest Publications
CPR Podcast Channel
AI Research
Web 3.0 Security
Intelligence Reports
ThreatCloud AI
Threat Intelligence & Research
Zero Day Protection
Sandblast File Analysis
About Us
SUBSCRIBE
2026
2025
2024
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2016
## 28th June – Threat Intelligence Report
For the latest discoveries in cyber research for the week of 28th June, please download our Threat Intelligence Bulletin .
Top Attacks and Breaches
Russian-based threat group Nobelium is using password spraying and brute force attacks to gain access to corporate networks. The group, which was behind the SolarWinds supply-chain attack, deployed an information-stealing Trojan on a Microsoft customer support agent’s computer to steal information. Over half of the targets were
https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CS5THZSGI7O2CZO44NWYE57AG2T7NK3K/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T7EAHJPWOOF4D6PEFLXW5IQWRRSZ3HRC/https://security.gentoo.org/glsa/202105-27https://security.netapp.com/advisory/ntap-20210219-0003/https://www.oracle.com/security-alerts/cpujan2021.htmlhttps://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/CS5THZSGI7O2CZO44NWYE57AG2T7NK3K/https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/T7EAHJPWOOF4D6PEFLXW5IQWRRSZ3HRC/https://security.gentoo.org/glsa/202105-27https://security.netapp.com/advisory/ntap-20210219-0003/https://www.oracle.com/security-alerts/cpujan2021.html
2021-01-20
Published