CVE-2026-48579Disclosure(microsoft / exchange_online)

LOWCVSS 7.5 · HIGH

Signal is active with 1 mentions in latest observed window

Immediate actions

Patch microsoft exchange_online systems immediately

Recommended action window: Monitor and triage in normal cycle

NVD description

Improper authorization in Microsoft Exchange Online allows an unauthorized attacker to disclose information over a network.

microsoft CVEs Back to dashboard

0.5/ 10 priority

Sources & remediation

Vendor / third-party advisories

https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-48579

Weakness type (CWE)

CWE-285

Priority

LOW

Exploitation

NONE

PoC

NONE

Patch

AVAILABLE

Momentum

STABLE

Are you affected?

If you run products in this scope, you should treat this CVE as relevant to your environment.

exchange_online

Threat summary

Patch or workaround signal is available
8 mentions across 5 observed days
Momentum state: stable

What's happening

Patch or workaround mentioned in 2 signals
Technical details provided in 5 signals
Disclosure: 5 classified signals
General: 1 classified signal
Peaked 3d ago at 3 mentions (2026-06-05); latest day: 1
8 total mentions across 5 days

Affected systems

Vendors

microsoft

Products

exchange_online

1 version affected across 1 product

Deep dive

Activity timeline8 mentions / 5d

Signal classification3 categories

Disclosure

562.5%

Patch

225.0%

General

112.5%

Referenced assets4 URLs

By indicator

Classification over time

Date	Total	Labels

2026-06-04	2	Disclosure2
2026-06-05	3	General1Patch2
2026-06-10	1	Disclosure1
2026-06-17	1	Disclosure1
2026-06-25	1	Disclosure1

Full discourse8 posts

Henrique Pereira@ikkebr124d
Disclosure
Earlier this year I set a goal to end the year with a couple CVEs to my name. So far, the year is going great: - CVE-2026-48579 (9.1 on MS Exchange) - CVE-2026-33102 (9.3 on M365 Copilot) - CVE-2026-21532 (8.2 on Azure Functions) - CVE-2026-44848 (9.4 on Portainer) - CVE-2026-55092 (8.0 on Trivy) Plus a plethora of other vulns I reported and got fixed without CVEs…
Post summary
The user announces that several new CVEs have been assigned to them across Microsoft and other platforms, indicating successful vulnerability discovery attempts.
0202242.0K
965 followersView on X
إبراهيم بوحيمد | Ibrahim Buhaimed@buhaimedi136d
Patch
ثغرتين في خدمات Microsoft السحابية بتقييم 10 و 9.1… وكلها تمت معالجتها وإغلاقها الثغرة الاولى في في Azure HorizonDB 📍 تقييمها CVSS 10 📍ـ CVE-2026-48567 نوعها Authentication Bypass by Spoofing. بإمكان مهاجم غير مصرح له تجاوز المصادقة عن طريق الانتحال، وبعدها يرفع صلاحياته عبر الشبكة. الثغرالثانية في Microsoft Exchange Online 📍 تقييمها CVSS 9.1 📍ـ CVE-2026-48579 نوعها Information Disclosure بسبب Improper Authorization. بإمكان مهاجم غير مصرح له يستغل خلل في الصلاحيات ويكشف معلومات عبر الشبكة. ـ Microsoft وضحت أن الثغرتين تم اغلاقهم طرفها ولايحتاج اي تدخل من قبل المستخدمين
Post summary
The post announces two Microsoft cloud CVEs, details their types and scores, and confirms that Microsoft has patched them, requiring no user action.
010851.3K
50.0K followersView on X
Orizon@OrizonCyber136d
Patch
🚨 CVE-2026-48579 — CVSS 9.1/10 █████████░ Improper authorization in Microsoft Exchange Online allows an unauthorized attacker to disclose information over a... Severity: CRITICAL Patch now. #cybersecurity #CVE https://t.co/mO4qqxGb4C
Post summary
CVE-2026-48579 is a critical improper‑authorization vulnerability in Microsoft Exchange Online with a CVSS 9.1/10 score; a patch has been released and is urged to be applied.
20000155
56 followersView on X
kawn@kawn2020131d
Disclosure
#windowsupdate #microsoft つづき・CVE-2026-47655　6.5　Microsoft Graph ・CVE-2026-48567　10　 Azure HorizonDB ・CVE-2026-48579　9.1　Microsoft Exchange Online －CVSS 基本値が 9.8 以上のもの：6 件・CVE-2026-26142　9.8　Nuance PowerScribe つづく…
Post summary
The tweet lists several newly disclosed CVEs along with their affected Microsoft components and CVSS base scores, providing basic vulnerability disclosure information.
1000085
85 followersView on X
IntegSec@integ_sec116d
Disclosure
CVE-2026-48579: Microsoft Exchange Online Information Disclosure Bug - What It Means for Your Business and How to Respond https://hubs.li/Q04mFPsd0
Post summary
The article announces the Microsoft Exchange Online information disclosure CVE-2026-48579 and discusses its potential business impact and response strategies.
0000061
31 followersView on X
VulDB 🛡@vuldb136d
General
It is possible to see elevated activities targeting Microsoft Exchange Online (CVE-2026-48579) https://vuldb.com/vuln/368417/cti
Post summary
The message notes the existence of elevated activity related to CVE‑2026‑48579 on Microsoft Exchange Online but offers no technical, exploit, or patch details.
0000070
2.2K followersView on X
VulDB 🛡@vuldb137d
Disclosure
A new vulnerability with increased severity was disclosed for Microsoft Exchange Online (CVE-2026-48579) https://vuldb.com/vuln/368417
Post summary
A new CVE (CVE-2026-48579) has been announced for Microsoft Exchange Online with increased severity, but the post lacks details on PoC, exploitation, patching, or active attacks.
00000106
2.2K followersView on X
WindowsForum@windowsforum137d
Disclosure
🪟 CVE-2026-48579: “Exchange Online info disclosure” = your data exposure isn’t waiting for your next reboot. Cloud vuln means monitoring + config triage now, not prayers later. #Windows #Microsoft #ExchangeOnline #SecurityUpdate https://windowsforum.com/threads/cve-2026-48579-exchange-online-info-disclosure-what-admins-should-do.422858/?utm_source=x&utm_medium=social&utm_campaign=news_node84 #InformationDisclosure https://t.co/A6jGgfrVDt
Post summary
The post announces a new information‑disclosure flaw in Exchange Online (CVE‑2026‑48579) and urges administrators to monitor and triage configurations, without providing a PoC, exploit, or patch information.
0000059
1.2K followersView on X

CPE platform detail1 entries

Part:

Vendor:

Product:

Version:

Target SW:

Target HW:

1 of 1 entries

Part	Vendor	Product	Version	Target SW	Target HW
App	microsoft	exchange_online	-	-	-

Explore more

Back to dashboard microsoft CVEs exchange_online vulnerabilities

What researchers are saying

CVE-2026-48579

Henrique Pereira[verified]@ikkebrDisclosure

The user announces that several new CVEs have been assigned to them across Microsoft and other platforms, indicating successful vulnerability discovery attempts.

إبراهيم بوحيمد | Ibrahim Buhaimed[verified]@buhaimediPatch

The post announces two Microsoft cloud CVEs, details their types and scores, and confirms that Microsoft has patched them, requiring no user action.

Orizon[verified]@OrizonCyberPatch

CVE-2026-48579 is a critical improper‑authorization vulnerability in Microsoft Exchange Online with a CVSS 9.1/10 score; a patch has been released and is urged to be applied.

IntegSec[verified]@integ_secDisclosure

The article announces the Microsoft Exchange Online information disclosure CVE-2026-48579 and discusses its potential business impact and response strategies.

WindowsForum[verified]@windowsforumDisclosure

The post announces a new information‑disclosure flaw in Exchange Online (CVE‑2026‑48579) and urges administrators to monitor and triage configurations, without providing a PoC, exploit, or patch information.

kawn@kawn2020Disclosure

The tweet lists several newly disclosed CVEs along with their affected Microsoft components and CVSS base scores, providing basic vulnerability disclosure information.

VulDB 🛡@vuldbGeneral

The message notes the existence of elevated activity related to CVE‑2026‑48579 on Microsoft Exchange Online but offers no technical, exploit, or patch details.

VulDB 🛡@vuldbDisclosure

A new CVE (CVE-2026-48579) has been announced for Microsoft Exchange Online with increased severity, but the post lacks details on PoC, exploitation, patching, or active attacks.