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CVE-2025-4918

An attacker was able to perform an out-of-bounds read or write on a JavaScript `Promise` object. This vulnerability affects Firefox < 138.0.4,...

Basic Information

CVE State
PUBLISHED
Reserved Date
May 17, 2025
Published Date
May 17, 2025
Last Updated
May 22, 2025
Vendor
Mozilla
Product
Firefox, Firefox ESR, Thunderbird
Description
An attacker was able to perform an out-of-bounds read or write on a JavaScript `Promise` object. This vulnerability affects Firefox < 138.0.4, Firefox ESR < 128.10.1, Firefox ESR < 115.23.1, Thunderbird < 128.10.2, and Thunderbird < 138.0.2.

CVSS Scores

CVSS v3.1

7.5 - HIGH

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

EPSS Score

Score
0.05% (Percentile: 13.81%) as of 2025-06-14

SSVC Information

Exploitation
none
Technical Impact
total

Exploit Status

Exploited in the Wild
Yes (2025-05-24 09:42:11 UTC) Source

References

https://bugzilla.mozilla.org/show_bug.cgi?id=1966612 https://www.mozilla.org/security/advisories/mfsa2025-36/ https://www.mozilla.org/security/advisories/mfsa2025-37/ https://www.mozilla.org/security/advisories/mfsa2025-38/ https://www.mozilla.org/security/advisories/mfsa2025-40/ https://www.mozilla.org/security/advisories/mfsa2025-41/

Known Exploited Vulnerability Information

Source Added Date
The Shadowserver (via CIRCL) 2025-05-24 12:00:16 UTC

Recent Mentions

Firefox Patches 2 Zero-Days Exploited at Pwn2Own Berlin with $100K in Rewards

Source: TheHackerNews • Published: 2025-05-19 10:37:00 UTC

Mozilla has released security updates to address two critical security flaws in its Firefox browser that could be potentially exploited to access sensitive data or achieve code execution. The vulnerabilities, both of which were exploited as a zero-day at Pwn2Own Berlin, are listed below - CVE-2025-4918 - An out-of-bounds access vulnerability when resolving Promise objects that could allow an

Timeline

  • CVE ID Reserved

  • CVE Published to Public

  • Added to KEVIntel