Mozilla fixes Firefox zero-days exploited at hacking contest

Mozilla fixes Firefox zero-days exploited at hacking contest

Mozilla issued urgent security patches for Firefox to fix two critical zero-day vulnerabilities revealed during Pwn2Own Berlin 2025. These updates protect the Firefox browser and ESR releases from potential exploitation by malicious actors. #Mozilla #Firefox

Keypoints

  • Two critical zero-day vulnerabilities were demonstrated during the Pwn2Own Berlin 2025 hacking competition.
  • The first flaw, CVE-2025-4918, involves an out-of-bounds read/write in the JavaScript engine when resolving Promise objects.
  • The second flaw, CVE-2025-4919, allows attackers to manipulate JavaScript objects by confusing array index sizes.
  • Mozilla quickly released security updates for Firefox desktop, Android, and ESR versions to mitigate these vulnerabilities.
  • While the flaws were demonstrated in a controlled environment, Mozilla warns they could be exploited in real-world attacks, emphasizing the importance of updating.

Read More: https://www.bleepingcomputer.com/news/security/mozilla-fixes-firefox-zero-days-exploited-at-hacking-contest/