Is CVE-2019-11707 actively exploited?

Yes. KEV Intelligence tracks CVE-2019-11707 as a known exploited vulnerability. Confidence is confirmed.

What exploitation activity has KEV Intelligence observed?

KEV Intelligence has not yet recorded sensor-observed exploitation attempts for CVE-2019-11707. Our sensors continue to monitor for activity targeting this CVE.

Which versions are affected?

CVE-2019-11707 affects Mozilla Firefox ESR and 2 other products. Reported affected versions include unspecified to < 60.7.1, unspecified to < 67.0.3, and unspecified to < 60.7.2.

Yes. CVE-2019-11707 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Vulnerability report

Exploited in the wild Confirmed confidence In CISA KEV

CVE-2019-11707

Q: How should organizations remediate it?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Q: Is it in CISA KEV?

Yes. CVE-2019-11707 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

Firefox ESR

Mozilla / Firefox ESR · affected before 60.7.1

View live feed Monitor via API Watch CVE

Severity: CVSS 8.8 · High
Confidence: Confirmed
Exploit status: Exploited in the wild
EPSS: 38.0%
First observed: —
Last observed: —

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2019-11707 is an unauthenticated vulnerability affecting Mozilla Firefox ESR and 2 other products. A type confusion vulnerability can occur when manipulating JavaScript objects due to issues in Array.pop. This can...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is confirmed.

Who is affected?

Mozilla / Firefox ESR affected before 60.7.1.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

A type confusion vulnerability can occur when manipulating JavaScript objects due to issues in Array.pop

A type confusion vulnerability can occur when manipulating JavaScript objects due to issues in Array.pop. This can allow for an exploitable crash.

We are aware of targeted attacks in the wild abusing this flaw. This vulnerability affects Firefox ESR < 60.7.1, Firefox < 67.0.3, and Thunderbird < 60.7.2.

Vendor Product Affected Status

Mozilla Firefox ESR Before 60.7.1 Affected

Mozilla Firefox Before 67.0.3 Affected

Mozilla Thunderbird Before 60.7.2 Affected

View vendor advisory

Published: 23 Jul 2019
Exploitation Reported: 23 May 2022
Attack vector: Remote
Complexity: Low
Privileges: None
User interaction: Required

CVE References

CVE Record CVE.org · CVE Record https://www.cve.org/CVERecord?id=CVE-2019-11707
GLSA-201908-12 security.gentoo.org · Vendor Advisory https://security.gentoo.org/glsa/201908-12
mozilla.org/security/advisories/mfsa2019-20 mozilla.org · CVE Record https://www.mozilla.org/security/advisories/mfsa2019-20/
mozilla.org/security/advisories/mfsa2019-18 mozilla.org · CVE Record https://www.mozilla.org/security/advisories/mfsa2019-18/
bugzilla.mozilla.org/show_bug.cgi bugzilla.mozilla.org · CVE Record https://bugzilla.mozilla.org/show_bug.cgi?id=1544386

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

CISA

Recorded 23 May 2022

Independent exploitation attestation added to the KEV Intelligence record.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

Learn about Pro API access

Source	Added
CISA First	2022-05-23 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets: 0
User-Agents: 0

Raw values available in Pro and Enterprise.

Scanner coverage

No scanner integrations recorded yet.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

No detection artifacts or sensor request patterns are available for this CVE yet.

Check back as sensor telemetry and scanner integrations are updated.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

8.8 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

EPSS

38.0%

Weaknesses

Access of Resource Using Incompatible Type ('Type Confusion') CWE-843

All CVSS Scores

CVSS v3.1 8.8 High

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

CVSS v2.0 7.5 High

AV:N/AC:L/Au:N/C:P/I:P/A:P

Timeline

From disclosure to observed exploitation

23 May 2022
Added to CISA KEV

Listed in the CISA Known Exploited Vulnerabilities catalog
23 Jul 2019
CVE published

Vulnerability disclosed publicly
03 May 2019
CVE ID reserved

Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

View Pro pricing Read API docs

Evidence confidence and provenance
First-party sensor telemetry
PoC and scanner references
Affected versions and enrichment
Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2019-11707

Free JSON includes basic KEV fields

{
  "cve_id": "CVE-2019-11707",
  "confidence": "Confirmed",
  "cvss_score": 8.8,
  "cvss_estimated": false,
  "epss_score": 0.37951,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

Early warning alerts

Get alerts on high-impact exploitation

Receive curator-selected alerts when exploitation activity warrants attention. Each alert includes the evidence and context needed to decide what requires attention now.