CVE-2026-50522 (GCVE-0-2026-50522)
Vulnerability from cvelistv5 – Published: 2026-07-14 17:05 – Updated: 2026-09-09 19:36- CWE-502 - Deserialization of Untrusted Data
| URL | Tags |
|---|---|
| https://msrc.microsoft.com/update-guide/vulnerabi… | vendor-advisorypatch |
| https://www.cisa.gov/known-exploited-vulnerabilit… | government-resource |
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Microsoft | Microsoft SharePoint Enterprise Server 2016 |
Affected:
16.0.0 , < 16.0.5561.1001
(custom)
|
guessed | |
| Microsoft | Microsoft SharePoint Server 2019 |
Affected:
16.0.0 , < 16.0.10417.20175
(custom)
|
guessed | |
| Microsoft | Microsoft SharePoint Server Subscription Edition |
Affected:
16.0.0 , < 16.0.19725.20434
(custom)
|
guessed |
CISA
Known Exploited Vulnerability - GCVE BCP-07 Compliant
Exploited: Yes
Timestamps
Scope
Evidence
Type: Vendor Report
Signal: Successful Exploitation
Confidence: 80%
Source: cisa-kev
Details
| Cwes | CWE-502 |
|---|---|
| Feed | CISA Known Exploited Vulnerabilities Catalog |
| Product | SharePoint |
| Due Date | 2026-07-25 |
| Date Added | 2026-07-22 |
| Vendorproject | Microsoft |
| Vulnerabilityname | Microsoft SharePoint Deserialization of Untrusted Data Vulnerability |
| Knownransomwarecampaignuse | Unknown |
References
Shadowserver
Known Exploited Vulnerability - GCVE BCP-07 Compliant
Exploited: Yes
Characteristics
Timestamps
Scope
Evidence
Type: Honeypot
Signal: In The Wild Attempts
Confidence: 70%
Source: shadowserver
Details
| 1D | 1 |
|---|---|
| Iot | no |
| Feed | Shadowserver Foundation honeypot/exploited-vulnerabilities |
| Type | http-scan |
| Class | file-transfer |
| 7D Avg | 2 |
| Vendor | Microsoft |
| 30D Avg | 3 |
| 90D Avg | 1 |
| Product | SharePoint |
| Cisa Kev | yes |
| Connections | 47 |
| Observation Date | 2026-09-07 |
| Vulnerability Class | CVSS |
| Vulnerability Score | 9.8 |
| Vulnerability Severity | Critical |
References
Previdian
Known Exploited Vulnerability - GCVE BCP-07 Compliant
Exploited: Yes
Timestamps
Scope
Evidence
Type: Public Report
Signal: Successful Exploitation
Confidence: 70%
Source: kevintel
Details
| Feed | KEVIntel (kevintel.com) |
|---|---|
| Title | Microsoft SharePoint Remote Code Execution Vulnerability |
| Vendor | Microsoft |
| Product | Microsoft SharePoint Enterprise Server 2016, Microsoft SharePoint Server 2019, Microsoft SharePoint Server Subscription Edition |
| Added Date | 2026-07-21T10:24:00.000Z |
| Cvss Score | 9.8 |
| Epss Score | 0.20346 |
| Cvss Severity | CRITICAL |
| Epss Percentile | 0.97202 |
| Used In Malware | unknown |
| Ahead Of Cisa Kev | None |
| Not Yet In Cisa Kev | True |
References
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Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.