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Threats / Google / CVE-2023-2136
CVE-2023-2136 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

Google Chromium Skia vulnerability

Integer overflow in Chromium Skia allows a compromised renderer process to escape the sandbox via crafted HTML, potentially enabling full system compromise.

Verdict

Today item — known-exploited.

A remote attacker who has already compromised the renderer process can exploit this integer overflow to break out of the sandbox. This escalates a renderer compromise into arbitrary code execution with browser privileges.

CISA KEV Yes · 2023-04-214EPSS 0.05739 (verify live)5CVSS 9.6 (CISA)3CISA SSVC Exploitation: active · Automatable: no · Impact: total3
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
7 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 2023-04-21).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.05739 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 9.6 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:H) · Affected: Google, Chromium Skia. Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
CISA-ADP ↗Reported
Weakness (CWE)
Mapped to CWE-190 Integer Overflow — weakness family: Memory safety.CWE assignment from the public NVD record (may be stale); the weakness class drives how the flaw is exploited.
NVD ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: no · Technical Impact: totalCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
CISA-ADP ↗Reported
Currency of the record
CISA added this to its KEV catalog 2 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
WeaknessCWE-190 · Integer OverflowMemory safety
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 malicious HTML that triggers an integer overflow in Skia's rendering logic.
Business
User visits a malicious webpage, triggering the vulnerability in their browser renderer.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I exploit the overflow to corrupt memory and bypass sandbox restrictions.
Business
The browser's security isolation layer is defeated, exposing the host system.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary code outside the sandbox with the privileges of the browser process.
Business
Attacker gains access to user data, system resources, and can pivot to further compromise the device.
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)
  • 7 reported-exploitation source(s)
  • CVSS 9.6 — CISA-assigned (CVE.org ADP)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping (NVD feed — CNA left none)
  • 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.