Security readout for executives and security teams
Plain-English summary
This is an old Windows-only Firefox local privilege escalation issue. A person who already has local access could abuse Mozilla’s Maintenance Service and updater path to run malicious local files with higher privileges. The source bundle says it affects Firefox versions before 50.
Executive priority
Treat this as a legacy endpoint hygiene issue unless old Firefox remains in production. Prioritize remediation where shared Windows workstations, kiosk systems, or unmanaged endpoints still run unsupported Firefox versions.
Technical view
CVE-2016-5295 concerns Mozilla Maintenance Service invoking Mozilla Updater in a way that can execute attacker-controlled local files. It is described as a variant of MFSA2013-44, requires local system access, affects Windows only, and applies to Firefox before version 50.
Likely exposure
Exposure is most likely on legacy Windows endpoints still running Firefox below version 50 with Mozilla Maintenance Service present. Modern supported Firefox deployments are unlikely to be affected based on the stated version boundary.
Exploitation context
The bundle does not cite CISA KEV listing or other evidence of active exploitation. Exploitation requires local system access first, so this is mainly a post-compromise or insider privilege escalation concern.
Researcher notes
The public bundle lacks CVSS, CWE, and detailed patch mechanics. Validation should focus on affected-version discovery and Windows service presence. Do not assume remote exploitability; the description explicitly requires local system access.
Mitigation direction
- Upgrade affected Windows Firefox installations to version 50 or later, preferably a supported current release.
- Retire unsupported Firefox versions from Windows endpoints.
- Review Mozilla MFSA2016-89 for vendor remediation guidance.
- Harden endpoint controls around local software tampering and untrusted file execution.
Validation and detection
- Inventory Windows endpoints for Firefox versions below 50.
- Identify systems where Mozilla Maintenance Service is installed with legacy Firefox.
- Confirm endpoint management prevents reintroduction of unsupported Firefox builds.
- Review privilege escalation alerts involving Firefox updater or Maintenance Service activity.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CVE-2016-5295 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://www.mozilla.org/en-US/security/advisories/mfsa2013-44/CVE reference · x_refsource_CONFIRM
- https://www.mozilla.org/security/advisories/mfsa2016-89/CVE reference · x_refsource_CONFIRM
- https://bugzilla.mozilla.org/show_bug.cgi?id=1247239CVE reference · x_refsource_CONFIRM
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.