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Threats / Meta Platforms / CVE-2025-55177
CVE-2025-55177 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Meta Platforms WhatsApp vulnerability

WhatsApp contains an authorization flaw in linked device synchronization that allows an unrelated user to trigger content processing from arbitrary URLs on a target device.

Verdict

Today item — known-exploited.

An attacker can exploit incomplete authorization checks on linked device messages to cause a target device to fetch and process content from attacker-controlled URLs, potentially enabling credential theft, malware delivery, or information disclosure.

CISA KEV Yes · 2025-09-023EPSS 0.04116 (verify live)4Exploit Weaponized · public PoC5
01

Is it exploitable?

— the evidence, ranked above the score
Exploit 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
8 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 2025-09-02).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.04116 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Meta Platforms, WhatsApp. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-863 Incorrect Authorization — weakness family: Authorization / access control.CWE assignment from the public NVD record; the weakness class drives how the flaw is exploited.
NVD ↗Reported
WeaknessCWE-863 · Incorrect AuthorizationAuthorization / access control
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 craft a malicious linked device synchronization message with a URL pointing to attacker-controlled content.
Business
Attackers gain a vector to deliver malware or phishing content to WhatsApp users without requiring direct contact or social engineering.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I send the message to a target whose device will process it due to missing authorization validation.
Business
The attack surface expands beyond authenticated contacts, increasing exposure across the user base.
3

Lateral reach — past segmentation narrative 3

Attacker
I host malicious content at the URL that the target device automatically fetches and processes.
Business
Sensitive data, credentials, or device integrity may be compromised through automatic content processing without user awareness.
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)
  • EPSS probability (FIRST)
  • Weaponized exploit available (VulnCheck)
  • 8 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by facebook (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 facebookCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.