SOC status:Duty analyst on shift

UK Cyber Defence
VulnerabilityModified

CVE-2017-5392

Weak proxy objects have weak references on multiple threads when they should only have them on one, resulting in incorrect memory usage and corruption, which leads to potentially exploitable crashes.

CRITICAL 9.8EPSS 1.73%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.73%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Weak proxy objects have weak references on multiple threads when they should only have them on one, resulting in incorrect memory usage and corruption, which leads to potentially exploitable crashes. Note: This issue only affects Firefox for Android. Other operating systems are not affected. This vulnerability affects Firefox < 51.

CVSS 3.0
9.8 CRITICALCVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS
1.73% probability · 78th percentile
Public exploits
None in Exploit-DB
CISA KEV
Not listed
Weakness
CWE-119
Affected
mozilla/firefox
Source
security@mozilla.org
EPSS trend
0%3%5%27 October 2026: 1.73%27 October 202627 October 2026

EPSS 1.7% since 27 October 2026; no change recorded yet. Points are recorded when the score first appears and whenever it moves by a percentage point or more.

Source: NVD record, EPSS from FIRST.org, KEV from CISA, exploits from Exploit-DB. Refreshed daily. Download this record as JSON.