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Threats / Microsoft / CVE-2025-49706
CVE-2025-49706 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Microsoft SharePoint vulnerability

Microsoft SharePoint contains an improper authentication vulnerability (CWE-287) allowing authorized attackers to spoof identity over a network, potentially viewing sensitive information and modifying disclosed data.

Verdict

Today item, not a backlog item.

An authenticated attacker can bypass authentication controls in SharePoint to impersonate other users or escalate privileges, gaining unauthorized access to sensitive information and making unauthorized modifications. This vulnerability is actively exploited in ransomware campaigns.

CISA KEV Yes · 2025-07-223Ransomware use Flagged3EPSS 0.99879 (verify live)4Exploit Public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
56 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2025-07-22), flagged for known ransomware use.
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.99879 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Microsoft, SharePoint. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-287 Improper Authentication — weakness family: Authentication.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I authenticate to SharePoint with valid credentials and exploit the improper authentication mechanism to spoof my identity as a higher-privileged user.
Business
Unauthorized access to sensitive SharePoint data and potential lateral movement within the organization increases breach risk and data exfiltration exposure.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I use my spoofed identity to access restricted documents and information repositories that should be protected from my actual privilege level.
Business
Confidential business information, intellectual property, and strategic documents are exposed to unauthorized disclosure and competitive harm.
3

Lateral reach — past segmentation narrative 3

Attacker
I modify or delete critical SharePoint content while appearing as a trusted administrator or authorized user, covering my tracks.
Business
Data integrity is compromised, audit trails are obscured, and business continuity is disrupted through unauthorized modifications or deletions of critical information.
4

Data at risk — exfiltration narrative 4

Attacker
I chain this vulnerability with CVE-2025-49704 to escalate my access and establish persistence within the SharePoint environment.
Business
The organization faces sustained compromise, enabling ransomware deployment, data encryption, and extortion demands from threat actors.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • Ransomware-use flag (CISA)
  • EPSS probability (FIRST)
  • Public PoC available (VulnCheck)
  • 56 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by microsoft (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by microsoftCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.