CVE-2016-9064: mozilla firefox Improper Certificate Validation
Vulnerability summary
CVE-2016-9064 is a medium (CVSS 5.9) Improper Certificate Validation vulnerability in mozilla firefox. EPSS estimates a 0.99% chance of exploitation in the next 30 days, higher than 62.6% of scored vulnerabilities.
Not severe (CVSS 5.9, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 11 · Related 6Timeline
- 11-06-2018PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
Description
Add-on updates failed to verify that the add-on ID inside the signed package matched the ID of the add-on being updated. An attacker who could perform a man-in-the-middle attack on the user's connection to the update server and defeat the certificate pinning protection could provide a malicious signed add-on instead of a valid update. This vulnerability affects Firefox ESR < 45.5 and Firefox < 50.
CVSS metrics
4 scores · 3 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
- OSV · DebianEcosystem advisory · calculated5.9MediumCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS trend
Probability
0.99%
Chance of exploitation in the next 30 days
Percentile
63%
Versus all other CVEs
30-day change
Decrease -0.02 pp
From 1.01% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication, no user interaction (CVSS vector). Other conditions: not stated in public data.
Mozilla2 products
- firefox≥ unspecified, < 50 | < 45.5.0 | < 50.0
- firefox esr≥ unspecified, < 45.5
Debian1 product
- firefox-esr< 45.5.0esr-1
Ubuntu1 product
- firefox< 50.0+build2-0ubuntu0.14.04.2 | < 50.0+build2-0ubuntu0.16.04.2
3 vendors · 4 products
