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Threats / WebKitGTK / CVE-2019-8720
CVE-2019-8720 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

WebKitGTK vulnerability

WebKitGTK contains a memory corruption vulnerability enabling remote code execution. The flaw has been exploited in the wild.

Verdict

Today item — known-exploited.

A memory corruption defect in WebKitGTK allows unauthenticated attackers to achieve remote code execution through crafted input, with confirmed active exploitation in the wild.

CISA KEV Yes · 2022-05-235EPSS 0.01543 (verify live)6CVSS 8.8 (CISA)4CISA SSVC Exploitation: active · Automatable: no · Impact: total4
01

Is it exploitable?

— the evidence, ranked above the score
Reported exploitation
1 independent public report of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
cisa.gov ↗Confirmed
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2022-05-23).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.01543 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 8.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H) · Affected: WebKitGTK, WebKitGTK. 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-119 Memory Buffer Bounds Error — weakness family: Memory safety.CWE — CNA-assigned (CVE.org); the weakness class drives how the flaw is exploited.
CVE.org ↗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 the same day 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.
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 web content designed to trigger a memory corruption flaw in WebKitGTK's processing logic.
Business
Users browsing untrusted websites or viewing attacker-controlled content face immediate code execution risk.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I deliver the exploit payload via a compromised website, email attachment, or embedded frame that the victim's browser processes.
Business
Attack surface spans all applications and services embedding WebKitGTK, multiplying exposure across desktop and embedded systems.
3

Lateral reach — past segmentation narrative 3

Attacker
I execute arbitrary code within the renderer process context, gaining the privileges of the browsing application.
Business
Attackers obtain direct access to user data, credentials, and system resources accessible to the compromised process.
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)
  • 1 reported-exploitation source(s)
  • CVSS 8.8 — CISA-assigned (CVE.org ADP)
  • CISA SSVC triage disposition (CVE.org ADP)
  • CWE weakness mapping — CNA-assigned (CVE.org)
  • Catalogued by redhat (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 redhatCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.