CVE-2019-17026: Zero-Day Vulnerability in Mozilla Firefox Exploited in Targeted Attacks
Mozilla releases patch to address Firefox flaw being used as part of targeted attacks.
Contexto
On January 8, Mozilla Foundation released a security advisory to address a critical zero-day flaw in Mozilla Firefox, which has been exploited in targeted attacks.
Análise
CVE-2019-17026 is a type confusion vulnerability in IonMonkey, the JavaScript Just-In-Time (JIT) compiler for SpiderMonkey, Mozilla’s JavaScript engine. According to Mozilla’s advisory, the flaw exists in the JIT compiler due to “incorrect alias information for setting array elements,” specifically in StoreElementHole and FallibleStoreElement.
The vulnerability was reported to Mozilla by researchers at Qihoo 360 ATA. Mozilla’s advisory states they are “aware of targeted attacks in the wild abusing this flaw.” Based on this note in the advisory, it appears the vulnerability was exploited in the wild as a zero-day. Further information about the exploitation was not available at the time this blog post was published.
This advisory follows the release of Firefox 72 and Firefox Extended Support Release (ESR) 68.4 on January 7, which included the following security advisories:
- Firefox 72: Mozilla Foundation Security Advisory 2020-01
- Firefox ESR 68.4: Mozilla Foundation Security Advisory 2020-02
Last year, Mozilla patched CVE-2019-11707, another type confusion flaw that was used in conjunction with CVE-2019-11708, a sandbox escape vulnerability in targeted attacks.
Prova de conceito
At this time, no proof of concept is available for this vulnerability.
Solução
To address CVE-2019-17026, Mozilla released Firefox 72.0.1 and Firefox ESR 68.4.1. Because this vulnerability has been exploited in targeted attacks, Firefox users are advised to upgrade as soon as possible.
Identificação de sistemas afetados
A list of Tenable plugins to identify this vulnerability will appear here as they’re released.
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Satnam Narang
Senior Staff Research Engineer, Security Response
Satnam entrou na Tenable em 2018. Ele tem mais de 15 anos de experiência no setor (M86 Security e Symantec). Ele contribuiu com o Anti-Phishing Working Group, ajudou a desenvolver um guia para redes sociais (Social Networking Guide) para a National Cyber Security Alliance, descobriu um botnet de spam importante no Twitter e foi o primeiro a reportar bots de spam no Tinder. Ele já participou do NBC Nightly News, Entertainment Tonight, Bloomberg West e no podcast Why Oh Why.
Interesses fora do trabalho: Satnam escreve poesia hip-hop. Ele gosta de música ao vivo e passar tempo com suas três sobrinhas, futebol e basquete, filmes e música de Bollywood e Grogu (Baby Yoda).
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