CVE-2016-2820: mozilla firefox Improper Access Control
Vulnerability summary
CVE-2016-2820 is a medium (CVSS 4.3) Improper Access Control vulnerability in mozilla firefox. EPSS estimates a 1.41% chance of exploitation in the next 30 days, higher than 72.6% of scored vulnerabilities.
Not severe (CVSS 4.3, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 30-04-2016PublishedVulnerability first disclosed.
- 05-08-2024Last modifiedVulnerability information updated.
Description
The Firefox Health Reports (aka FHR or about:healthreport) feature in Mozilla Firefox before 46.0 does not properly restrict the origin of events, which makes it easier for remote attackers to modify sharing preferences by leveraging access to the remote-report IFRAME element.
CVSS metrics
3 scores · 2 sources · 2 versions- OSV · UbuntuEcosystem advisory · calculated4.3MediumCVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
EPSS trend
Probability
1.41%
Chance of exploitation in the next 30 days
Percentile
73%
Versus all other CVEs
30-day change
No change 0.00 pp
From 1.41% 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, user interaction (CVSS vector). Other conditions: not stated in public data.
Mozilla1 product
- firefox≤ 45.0.2
Ubuntu1 product
- firefox< 46.0+build5-0ubuntu0.14.04.2 | < 46.0+build5-0ubuntu0.16.04.2
2 vendors · 2 products
References
13 links- bugzilla.mozilla.org/show_bug.cgi?id=870870X Refsource CONFIRM