NVD / CVE Program· CNA microsoft

CVE-2020-0688: A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, ak

Noroxi assessment

Priority: Now (action score 95/100)

CISA has confirmed exploitation in the wild (Nov 3, 2021); it is known to be used in ransomware campaigns. Remediation deadline for US federal agencies: May 3, 2022.
A ready-made attack module is public (Metasploit); exploiting it takes no special expertise.
Probability of exploitation in the next 30 days: 99.9% (FIRST EPSS); higher than 99.9% of all records.
Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
According to the record, no fixed version is available yet.
Mentioned 3 times in Turkish national cyber security advisories (siberguvenlik.gov.tr).

Patch today or shut off access. Until a fix is released, restrict access to the affected component and follow the vendor's advisory.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · CISA KEV · FIRST EPSS

A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, aka 'Microsoft Exchange Memory Corruption Vulnerability'.

HighCVSS 8.8 · v3.1KEVWeaponized No fix recorded

BDU:2020-00948

Published: Feb 11, 2020
Updated: Jun 16, 2026
EPSS: 99.9% · 99th percentile
CWE: CWE-287

Report tools

JSON

Action score

Now

Patch today or shut off access.

CVSS: 35 / 40 · 8.8 / 10
CISA KEV: 30 / 30 · Listed
EPSS: 30 / 30 · 99.9%

CISA SSVC decision

Exploitation: active
Automatable: no
Technical impact: total

Vulnrichment: CISA's decision-tree inputs.

Actively exploited in the wild

CISA added this to its Known Exploited Vulnerabilities catalog on Nov 3, 2021. That signals real attacks, not theory.

Remediation deadline for US federal agencies: May 3, 2022.

Known to be used in ransomware campaigns.

Get told when this record changes

In CISA KEV: exploitation in the wild confirmed
Weaponized exploit exists
No fixed version yet

If any of these changes, we'll tell you in the daily email digest.

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
microsoft	exchange server	cpe:2.3:a:microsoft:exchange_server

Using exchange server? Add it to your stack and be the first to know about CVEs like this one. (Email server)

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

microsoft exchange server2010
microsoft exchange server2013
microsoft exchange server2016
microsoft exchange server2019

Versions reported by the vendor

Affected version ranges reported by the assigning authority (microsoft). Independent of NVD's CPE analysis and usually ahead of it.

Microsoft Microsoft Exchange Server 2010 Service Pack 3 Update Rollup 30
- unspecifiedaffected
Microsoft Microsoft Exchange Server 2013
- Cumulative Update 23affected
Microsoft Microsoft Exchange Server 2016 Cumulative Update 14
- unspecifiedaffected
Microsoft Microsoft Exchange Server 2016 Cumulative Update 15
- unspecifiedaffected
Microsoft Microsoft Exchange Server 2019 Cumulative Update 3
- unspecifiedaffected
Microsoft Microsoft Exchange Server 2019 Cumulative Update 4
- unspecifiedaffected

Same product

microsoft: all records

Other highest-scoring records for the same primary product.

CVE-2021-34523Microsoft Exchange Server Elevation of Privilege VulnerabilityKEV
96Now
CVE-2021-34473Microsoft Exchange Server Remote Code Execution VulnerabilityKEV
96Now
CVE-2021-26855Microsoft Exchange Server Remote Code Execution VulnerabilityKEV
96Now

Published before and after this one in the same product

← EarlierCVE-2019-1266Sep 11, 2019 · A spoofing vulnerability exists in Microsoft Exchange Server when Outlook Web App (OWA) fails to properly handle web requests, aka 'Microsof
25Monitor
← EarlierCVE-2019-1373Nov 12, 2019 · A remote code execution vulnerability exists in Microsoft Exchange through the deserialization of metadata via PowerShell, aka 'Microsoft Ex
46Plan
Later →CVE-2020-0692Feb 11, 2020 · An elevation of privilege vulnerability exists in Microsoft Exchange Server, aka 'Microsoft Exchange Server Elevation of Privilege Vulnerabi
33Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

No fix version is recorded for this entry. Check the references for vendor advisories.

Exploit status

Weaponized

A ready exploit tool or active in-the-wild use is known for this vulnerability. This should be your top priority.

Evidence

Metasploit module ×1
Exploit-DB entry ×2
Proof-of-concept repository on GitHub ×25

Noroxi does not host or link to exploit code. Metasploit module names and Nuclei template ids are shown (names, not code); Exploit-DB entries and PoC repositories are given as counts only.

Public exploit evidence
Source	Kind	Date
Exploit-DB entry	remote	2020-03-05
Exploit-DB entry	remote	2020-03-02
Metasploit module	exploit/windows/http/exchange_ecp_viewstateExchange Control Panel ViewState Deserializationexploit	2020-02-11
Proof-of-concept repository on GitHub	stars:165	2020-02-25
Proof-of-concept repository on GitHub	stars:66	2020-02-26
Proof-of-concept repository on GitHub	stars:327	2020-02-27
Proof-of-concept repository on GitHub	stars:144	2020-02-27
Proof-of-concept repository on GitHub	stars:1	2020-02-28
Proof-of-concept repository on GitHub	stars:37	2020-02-28
Proof-of-concept repository on GitHub	stars:10	2020-02-28
Proof-of-concept repository on GitHub	stars:354	2020-03-01
Proof-of-concept repository on GitHub	stars:5	2020-03-04

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

MetasploitFeb 11, 2020-1 d
PublishedFeb 11, 2020
First PoCFeb 25, 2020+13 d
CISA KEVNov 3, 2021+630 d
TodayNov 1, 2026+2455 d

No history yet (it accumulates with the daily EPSS job).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

National notice (Türkiye Cybersecurity Directorate / USOM)

Official security notices citing this record; remediation advice is on the agency's page.

TR-20-690 · Sep 9, 2020(Microsoft Eylül 2020 Güvenlik Güncellemelerini Yayınladı)
TR-20-262 · Apr 23, 2020(Uzaktan Erişim Servislerine Yönelik Önlemler)
TR-20-135 · Mar 10, 2020(Microsoft Exchange Sunucu Güvenlik Güncellemesi)

All national notices →

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
A low-privileged account is enough.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: Low
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-287 · Improper Authentication

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.

The bug in code

The whole CWE-287 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1app.use("/admin", requireSession, adminRouter);
2

3// Route added later skips the middleware
4app.post("/admin-api/config", updateConfig);

Fixed

1const admin = express.Router();
2admin.use(requireSession, requireRole("admin"));
3

4admin.post("/config", updateConfig);
5app.use("/admin", admin);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

Change log

No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.

References

portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2020-0688

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records

Noroxi analysis

What does it mean in your environment?

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Data sources and verification

CNA: microsoft

CVE.org (CNA)Oct 21, 2025, 11:35 PM UTC
CISA ADPOct 21, 2025, 11:35 PM UTC
NVDJun 16, 2026, 10:46 PM UTC
FIRST EPSSOct 29, 2026, 12:00 AM UTC
Exploit-DBNov 1, 2026, 3:18 AM UTC
MetasploitNov 1, 2026, 3:18 AM UTC
PoC-in-GitHubNov 1, 2026, 3:18 AM UTC

Each line is when that source was last processed for this record.

CVE-2020-0688: A remote code execution vulnerability exists in Microsoft Exchange software when the software fails to properly handle objects in memory, ak

Noroxi assessment

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Affected systems

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Affected versions

Versions reported by the vendor

Same product

Remediation

Which version to upgrade to

Exploit status

Research context

Timeline

Patch and commit links

Credits

Variant candidates

Chain candidates

National notice (Türkiye Cybersecurity Directorate / USOM)

Technical details

Attack conditions

If successful

Root cause

The bug in code

Attack context

Change log

References