Threats / Microsoft / CVE-2019-0604
CVE-2019-0604
· EUVD no mirror located
· GCVE no mirror located
Verified 2026-06-22
Microsoft SharePoint vulnerability
Microsoft SharePoint fails to validate application package source markup, allowing remote code execution in the SharePoint application pool and farm account context.
Verdict
Today item, not a backlog item.
An unauthenticated or low-privileged attacker can exploit improper input validation in SharePoint application packages to achieve remote code execution with elevated privileges, enabling full server compromise and lateral movement within the farm.
CISA KEV Yes · 2021-11-033Ransomware use Flagged3EPSS 0.99913 (verify live)4Exploit Weaponized · public PoC5
01
Is it exploitable?
— the evidence, ranked above the scoreExploit available
Fully weaponized — public exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
32 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 2021-11-03), flagged for known ransomware use.
Probability (EPSS)
EPSS 0.99913 — 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.
Weakness (CWE)
Mapped to CWE-20 Improper Input Validation.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
02
Who’s exploiting it?
— attribution turns risk into urgencyAttribution 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 board1
Front door — unauthenticated access narrative 1
Attacker
I craft a malicious application package with invalid or malicious source markup that bypasses validation checks.
Business
Attackers gain initial foothold to deploy ransomware or establish persistent access across SharePoint infrastructure.
2
Keys to the kingdom — privilege/identity takeover narrative 2
Attacker
I upload or deploy the crafted package to a vulnerable SharePoint server.
Business
The attack surface includes any organization using SharePoint, with no patch required for exploitation in unpatched systems.
3
Lateral reach — past segmentation narrative 3
Attacker
I execute arbitrary code within the SharePoint application pool and farm account security context.
Business
Attackers inherit the privileges of the SharePoint service account, typically a high-value target with broad farm permissions.
4
Data at risk — exfiltration narrative 4
Attacker
I move laterally to other servers in the SharePoint farm and connected infrastructure using compromised credentials.
Business
Entire SharePoint deployments and dependent systems become compromised, enabling data exfiltration and operational disruption.
5
Lights out — disruption & extortion narrative 5
Attacker
I deploy ransomware or maintain persistent backdoor access for long-term exploitation.
Business
Organizations face extended downtime, data loss, ransom demands, and regulatory compliance violations affecting business continuity.
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