CVE-2019-11708
CVE-2019-11708 is a security flaw in Mozilla Firefox and Thunderbird, Mozilla’s web browser. Attackers can run their own code on Mozilla Firefox and Thunderbird. The US Cybersecurity and Infrastructure Security Agency (CISA) added it to its catalog of flaws known to be used in attacks on 23 May 2022.[1]
Mozilla Firefox and Thunderbird is in things households have, such as phones, computers, browsers and everyday apps, so the fix matters at home as much as at work. Fixed in version 60.7.2 and 67.0.4.
Description
CISA calls it a sandbox escape in Mozilla Firefox and Thunderbird. In its words: “Mozilla Firefox and Thunderbird contain a sandbox escape vulnerability that could result in remote code execution.”[1]
The CVE record adds: “Insufficient vetting of parameters passed with the Prompt:Open IPC message between child and parent processes can result in the non-sandboxed parent process opening web content chosen by a compromised child process. When combined with additional vulnerabilities this could result in executing arbitrary code on the user's computer. This vulnerability affects Firefox ESR < 60.7.2, Firefox < 67.0.4, and Thunderbird < 60.7.2.”[2]
The underlying weakness is improper input validation (CWE-20), in MITRE’s list of common software weaknesses.
It scores 10.0 out of 10 on the Common Vulnerability Scoring System, which rates it critical, scored by NVD using CVSS 3.1.[2]
Affected versions
NVD’s record lists these fixed versions: in each line, everything before the version shown is affected.[2]
| Product | Fixed in |
|---|---|
| Firefox ESR | 60.7.2 |
| Firefox | 67.0.4 |
| Thunderbird | 60.7.2 |
Every device with Mozilla Firefox and Thunderbird needs the update.
Exploitation
CISA added it to its catalog of known exploited vulnerabilities on 23 May 2022, 1,035 days after it was made public. CISA lists a flaw only when it has reliable evidence of it being exploited, and gave US federal agencies until 13 Jun 2022 to fix it.[1]
FIRST’s Exploit Prediction Scoring System, which estimates how likely a flaw is to be used in attacks in the next 30 days from what it sees across the internet, puts it at 56%. That’s in the top 1% of the flaws it scores.[4]
CISA assesses it as not automatable: each attack takes some work.
CISA doesn’t say who was attacked, or how.
Fix
Mozilla has published a fix or advice.[3] CISA’s required action: “Apply updates per vendor instructions.”[1]
- Update Mozilla Firefox and Thunderbird now.Install the latest update from Mozilla on every device that has it, and restart when asked. Then turn on automatic updates, so the next fix arrives on its own.
- Check you’re on 60.7.2 or later.Fixed in version 60.7.2 and 67.0.4. Anything older is what attackers are going after.
- If there’s no update, stop using it.CISA’s advice when a flaw being used in attacks has no fix is to stop using the product until it does.
Timeline
| Date | Event |
|---|---|
| The flaw is made public in the National Vulnerability Database, with a severity score of 10.0.[2] | |
| CISA adds it to its catalog of flaws known to be used in attacks.[1] | |
| CISA’s deadline for US government agencies to fix it.[1] | |
| FIRST puts the odds of it being used in attacks in the next 30 days at 56%.[4] |
See also
Other Mozilla Firefox and Thunderbird flaws
- CVE-2019-11707: type confusion ·
- CVE-2013-1690: denial-of-service ·
- CVE-2020-6820: use-after-free ·
- CVE-2020-6819: use-after-free ·
- CVE-2019-17026: type confusion ·
Other Mozilla flaws
- CVE-2010-3765, Mozilla products: remote code execution ·
- CVE-2024-9680, Mozilla Firefox: use-after-free ·
- CVE-2016-9079, Mozilla Firefox, Firefox ESR, and Thunderbird: use-after-free ·
- CVE-2015-4495, Mozilla Firefox: security feature bypass ·
- CVE-2022-26486, Mozilla Firefox: use-after-free ·
Other improper input validation flaws
- CVE-2026-93952, Arista VeloCloud Orchestrator: improper input validation ·
- CVE-2019-1068, Microsoft SQL Server: remote code execution ·
- CVE-2026-12569, PTC Windchill and FlexPLM: improper input validation ·
- CVE-2026-34910, Ubiquiti UniFi OS: improper input validation ·
- CVE-2026-6973, Ivanti Endpoint Manager Mobile (EPMM): improper input validation ·
Added the same day
- CVE-2022-20821, Cisco IOS XR: open port ·
- CVE-2021-30883, Apple devices: memory corruption ·
- CVE-2021-1048, Android Kernel: use-after-free ·
- CVE-2021-0920, Android Kernel: race condition ·
- CVE-2020-1027, Microsoft Windows: kernel privilege escalation ·
Every Mozilla flaw on CISA’s list · Everything added in May 2022
References
- ^ Cybersecurity and Infrastructure Security Agency. “Mozilla Firefox and Thunderbird Sandbox Escape Vulnerability”. Known Exploited Vulnerabilities Catalog, added 23 May 2022.
- ^ National Institute of Standards and Technology. “CVE-2019-11708 Detail”. National Vulnerability Database, published 23 Jul 2019.
- ^ Mozilla. Advisories and fixes: bugzilla.mozilla.org, mozilla.org, mozilla.org.
- ^ FIRST. “Exploit Prediction Scoring System”. EPSS 0.559, percentile 99.0, 31 Oct 2026.
- CVE Program. “CVE-2019-11708”. The official CVE record.
This article is built from CISA’s catalog (version 2026.10.30), NVD’s record and FIRST’s scores, kept in HARD’s database and checked every morning. The plain English is HARD’s.