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Threats / Google / CVE-2025-6558
CVE-2025-6558 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Google Chromium vulnerability

Chromium contains an improper input validation flaw in ANGLE and GPU processing that permits sandbox escape via crafted HTML, affecting Chrome, Edge, and other Chromium-based browsers.

Verdict

Today item — known-exploited.

Remote attacker can bypass browser sandbox isolation by delivering malicious HTML to a victim, potentially achieving code execution outside the sandbox boundary. Active exploitation observed in the wild.

CISA KEV Yes · 2025-07-223EPSS 0.09524 (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
9 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).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.09524 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Google, Chromium. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
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.
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 craft a malicious HTML page exploiting improper GPU input validation in ANGLE.
Business
User visits attacker-controlled or compromised website, triggering vulnerability during page render.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I trigger the input validation flaw to escape the browser sandbox isolation.
Business
Attacker gains execution context outside sandbox, bypassing primary browser security boundary.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary code with elevated privileges on the victim's system.
Business
Attacker can access user files, credentials, and system resources; potential for lateral movement and persistent compromise.
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)
  • Public PoC available (VulnCheck)
  • 9 reported-exploitation source(s)
  • CWE weakness mapping (NVD)
  • Public exploit availability
  • Catalogued by Chrome (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 ChromeCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.