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CVE-2019-11707

Mozilla Firefox and Thunderbird Type Confusion

8.8 HIGHActively exploited (CISA KEV)EPSS 37.7%
  1. Published23 Jul 2019
  2. Added to CISA KEV23 May 2022
  3. Remediation due13 Jun 2022
Actively exploited (CISA KEV)

Mozilla Firefox and Thunderbird contain a type confusion vulnerability that can occur when manipulating JavaScript objects due to issues in Array.pop, allowing for an exploitable crash.

Added to KEV: 23 May 2022Federal remediation due: 13 Jun 2022

Description

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.

CVSS 3.1 breakdown

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionRequired
ScopeUnchanged
ConfidentialityHigh
IntegrityHigh
AvailabilityHigh
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected products

Mozilla Firefox< 67.0.3 · < 60.7.1
Mozilla Thunderbird< 60.7.2

Remediation

Fixed in
Mozilla Firefox≥ 67.0.3
Mozilla Thunderbird≥ 60.7.2

References

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Frequently asked

Is CVE-2019-11707 being actively exploited?

Yes. CVE-2019-11707 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 23 May 2022.

How severe is CVE-2019-11707?

CVE-2019-11707 has a CVSS 3.1 base score of 8.8, rated high. EPSS estimates a 37.7% probability of exploitation.

Which products are affected by CVE-2019-11707?

Affected products include Mozilla Firefox, Mozilla Thunderbird.

How do I fix CVE-2019-11707?

Upgrade affected software to a fixed version, for example Mozilla Firefox 67.0.3, Mozilla Thunderbird 60.7.2 or later, then confirm no affected versions remain in your inventory.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2019-11707 against the real software inventory on every managed device, as each hourly inventory arrives. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, a risk for it never ranks below high, and the update that fixes it moves to the Emergency patch lane. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.