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Threats / Google / CVE-2025-5419
CVE-2025-5419 · EUVD no mirror located · GCVE no mirror located Verified 2026-06-22

Google Chromium V8 vulnerability

Google Chromium V8 contains out-of-bounds read and write vulnerabilities allowing remote code execution through crafted HTML pages, affecting multiple browsers including Chrome, Edge, and Opera.

Verdict

Today item — known-exploited.

A remote attacker can exploit heap corruption in V8 by delivering a malicious HTML page to an unsuspecting user, potentially achieving arbitrary code execution within the browser process with the privileges of the user.

CISA KEV Yes · 2025-06-053EPSS 0.06463 (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 2025-06-05).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.06463 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
Affected: Google, Chromium V8. Confirm exact fixed builds in the vendor advisory.
NVD ↗Reported
Weakness (CWE)
Mapped to CWE-125 Out-of-bounds Read, CWE-787 Out-of-bounds Write — weakness family: Memory safety.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 that triggers out-of-bounds memory access in V8's JavaScript engine.
Business
User browsers crash or become unstable, degrading service availability and user experience.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I exploit the heap corruption to read sensitive data from browser memory, such as authentication tokens or cached credentials.
Business
User credentials and session data are compromised, leading to account takeovers and data breaches.
3

Lateral reach — past segmentation narrative 3

Attacker
I leverage the write vulnerability to inject and execute arbitrary code within the browser process.
Business
Attackers gain code execution on user systems, enabling malware installation, data theft, and lateral movement to internal networks.
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.