CVE-2026-55005

highpriority · track · 0EPSS 0.010 · 63 %ileDEEUNLUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

1.01% (63rd) EPSS

CVSS 8.8 · high

Is it mine?

23 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · cert_bund · msrc_csaf

EPSS · scored 2026-10-27

Heap-based buffer overflow in Microsoft Exchange Server allows an authorized attacker to execute code over a network.

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
15.01.2507.071:Security Update:https://support.microsoft.com/help/5103215
https://support.microsoft.com/help/5103215
FixedMicrosoft Exchange Server 2019 Cumulative Update 14msrc_csaf
15.02.1544.043:Security Update:https://support.microsoft.com/help/5103214
https://support.microsoft.com/help/5103214
FixedMicrosoft Exchange Server 2019 Cumulative Update 15msrc_csaf
15.02.1748.048:Security Update:https://support.microsoft.com/help/5103213
https://support.microsoft.com/help/5103213
FixedMicrosoft Exchange Server Subscription Edition RTMmsrc_csaf
15.02.2562.045:Security Update:https://support.microsoft.com/help/5103212
https://support.microsoft.com/help/5103212

cvss

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

8.8

010

base score 0–10 · higher = more severe · hover a vector to decode

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · ENISA EU

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:Hsecondary · secure@microsoft.com USexploitability 2.8 · impact 5.9

v3.18.1highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H/E:U/RL:O/RC:Csecondary · NCSC-NL NL

v3.18.8highCVSS:3.1/AV:N/AC:L/PR:L/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: no · Technical Impact: totalcoordinatorcisa_ssvcUS

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-122USCWE-122USCWE-122US

affected products (23)

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 14all versionscert_bundDEcpe:/a:microsoft:exchange:server_2019_cumulative_update_14
Microsoft Exchange Server Subscription Edition RTMall versionscert_bundDEcpe:/a:microsoft:exchange:server_subscription_edition_rtm
Microsoft Microsoft Exchange Server 2016 Cumulative Update 2315.01.0.0 → 15.01.2507.071enisa_euvdEU
Microsoft Microsoft Exchange Server 2019 Cumulative Update 1415.02.0.0 → 15.02.1544.043enisa_euvdEU
Microsoft Microsoft Exchange Server 2019 Cumulative Update 1515.02.0.0 → 15.02.1748.048enisa_euvdEU
Microsoft Microsoft Exchange Server Subscription Edition RTM15.02.0.0 → 15.02.2562.045enisa_euvdEU
Microsoft Microsoft Exchange Server 2016 Cumulative Update 23all versionsfixedmsrc_csafUS
Microsoft Microsoft Exchange Server 2016 Cumulative Update 23< 15.01.2507.071msrc_csafUS
Microsoft Microsoft Exchange Server 2019 Cumulative Update 14all versionsfixedmsrc_csafUS
Microsoft Microsoft Exchange Server 2019 Cumulative Update 14< 15.02.1544.043msrc_csafUS
Microsoft Microsoft Exchange Server 2019 Cumulative Update 15all versionsfixedmsrc_csafUS
Microsoft Microsoft Exchange Server 2019 Cumulative Update 15< 15.02.1748.048msrc_csafUS
Microsoft Microsoft Exchange Server Subscription Edition RTMall versionsfixedmsrc_csafUS
Microsoft Microsoft Exchange Server Subscription Edition RTM< 15.02.2562.045msrc_csafUS
Microsoft Microsoft Exchange Online≤ vers:unknown/*ncsc_nlNL
Microsoft Microsoft Exchange Server 2016 Cumulative Update 23≤ vers:unknown/*ncsc_nlNL
Microsoft Microsoft Exchange Server 2019 Cumulative Update 14≤ vers:unknown/*ncsc_nlNL
Microsoft Microsoft Exchange Server 2019 Cumulative Update 15≤ vers:unknown/*ncsc_nlNL
Microsoft Microsoft Exchange Server Subscription Edition RTM≤ vers:unknown/*ncsc_nlNL

showing 20 of 23

advisories (3)

Vendor and ecosystem advisories describing this.

NCSC-2026-0234Kwetsbaarheden verholpen in Microsoft ExchangeNL2026-07-14csaf · ncsc_nlNL
Microsoft heeft kwetsbaarheden verholpen in Exchange, zowel Online als on-premise.
WID-SEC-W-2026-2326Microsoft Exchange: Mehrere SchwachstellenDeutsch2026-07-14csaf · cert_bundDE
Ein Angreifer kann mehrere Schwachstellen in Microsoft Exchange ausnutzen, um beliebigen Programmcode auszuführen, erweiterte Berechtigungen zu erlangen oder Spoofing-Angriffe durchzuführen.
msrc_CVE-2026-55005Microsoft Exchange Server Remote Code Execution Vulnerability2026-07-14csaf · msrc_csafUS
To determine the support lifecycle for your software, see the Microsoft Support Lifecycle: https://support.microsoft.com/lifecycle

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd cert_bund msrc_csaf ncsc_nl NVD CVE.org MITRE

published 2026-07-14modified 2026-07-24

references (3)

External citations — patches, advisories, analysis.

scry

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