CVE-2023-21709

highpriority · track · 1EPSS 0.020 · 80 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.98% (80th) EPSS

CVSS 8.8 · high

Is it mine?

17 products

Check your exposure

Who says so?

6 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

Microsoft Exchange Server Elevation of Privilege Vulnerability

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

FixedMicrosoft Exchange Server 2016 Cumulative Update 23msrc_csaf
15.01.2507.032:Security Update:https://support.microsoft.com/help/5030524
https://support.microsoft.com/help/5030524
FixedMicrosoft Exchange Server 2019 Cumulative Update 12msrc_csaf
15.02.1118.037:Security Update:https://support.microsoft.com/help/5030524
https://support.microsoft.com/help/5030524
FixedMicrosoft Exchange Server 2019 Cumulative Update 13msrc_csaf
15.02.1258.025:Security Update:https://support.microsoft.com/help/5030524
https://support.microsoft.com/help/5030524

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 8.8–9.8

v3.18.8highAV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · FSTEC (BDU) RU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · ENISA EU

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 3.9 · impact 5.9

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · Microsoft Security Response Center US

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-307USprimaryCWE-264USCWE-307US

affected products (17)

Products and version ranges known to be affected.

Microsoft Exchange Server 2016 Cumulative Update 23all versionscert_bundDEcpe:/a:microsoft:exchange_server_2016:cumulative_update_23
Microsoft Exchange Server 2019 Cumulative Update 12all versionscert_bundDEcpe:/a:microsoft:exchange_server_2019:cumulative_update_12
Microsoft Exchange Server 2019 Cumulative Update 13all versionscert_bundDEcpe:/a:microsoft:exchange_server_2019:cumulative_update_13
Microsoft Microsoft Exchange Server 2016 Cumulative Update 2315.01.0 → 15.01.2507.032enisa_euvdEU
Microsoft Microsoft Exchange Server 2019 Cumulative Update 1215.02.0 → 15.02.1118.037enisa_euvdEU
Microsoft Microsoft Exchange Server 2019 Cumulative Update 1315.02.0 → 15.02.1258.025enisa_euvdEU
Microsoft Corp Microsoft Exchange Server≤ 2016 Cumulative Update 23fstec_bduRU
Microsoft Corp Microsoft Exchange Server≤ 2019 Cumulative Update 13fstec_bduRU
Microsoft Corp Microsoft Exchange Server≤ 2019 Cumulative Update 12fstec_bduRU
Microsoft Exchange Server 2016 Cumulative Update 23all versionsfixedmsrc_csafUS
Microsoft Exchange Server 2016 Cumulative Update 23< 15.01.2507.032msrc_csafUS
Microsoft Exchange Server 2019 Cumulative Update 12all versionsfixedmsrc_csafUS
Microsoft Exchange Server 2019 Cumulative Update 12< 15.02.1118.037msrc_csafUS
Microsoft Exchange Server 2019 Cumulative Update 13all versionsfixedmsrc_csafUS
Microsoft Exchange Server 2019 Cumulative Update 13< 15.02.1258.025msrc_csafUS
microsoft exchange server= 2016nvdUScpe:2.3:a:microsoft:exchange_server:*:*:*:*:*:*:*:*
microsoft exchange server= 2019nvdUScpe:2.3:a:microsoft:exchange_server:*:*:*:*:*:*:*:*

advisories (2)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2023-1990Microsoft Exchange Server: Mehrere SchwachstellenDeutsch2023-08-08csaf · cert_bundDE
Ein entfernter, anonymer Angreifer kann mehrere Schwachstellen in Microsoft Exchange Server 2016 und Microsoft Exchange Server 2019 ausnutzen, um seine Privilegien zu erhöhen, beliebigen Programmcode auszuführen oder Dateien zu manipulieren.
msrc_CVE-2023-21709Microsoft Exchange Server Elevation of Privilege Vulnerability2023-08-08csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (4)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund msrc_csaf nvd NVD CVE.org MITRE

published 2023-08-08modified 2026-08-10

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+820 more

references (5)

External citations — patches, advisories, analysis.

scry

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