Security readout for executives and security teams
Plain-English summary
This Firefox flaw let code escape intended sandbox file-system limits and gain read/write access to the local file system. For organizations still running Firefox before 53 or Firefox ESR before 52.1, the business concern is unauthorized local file access from a browser security boundary failure.
Executive priority
Treat this as a legacy-browser remediation issue with high impact if affected versions remain in use. Prioritize discovery and removal of outdated Firefox builds, especially on endpoints handling sensitive data or privileged workflows.
Technical view
CVE-2017-5456 is a Mozilla sandbox bypass involving the file system request constructor through an IPC message. The public description states it can bypass file system access protections and allow local file read and write access. Affected versions are Firefox ESR before 52.1 and Firefox before 53.
Likely exposure
Exposure is most likely on legacy endpoints or managed environments retaining Firefox ESR below 52.1 or Firefox below 53. Current supported Firefox installations should not be assumed affected based on the provided sources.
Exploitation context
The provided bundle does not show CISA KEV listing or cited evidence of active exploitation. Public references identify the vulnerability and affected Mozilla versions, but do not provide a CVSS score, exploit maturity, or confirmed exploitation details.
Researcher notes
The source bundle supports impact, affected version bounds, and vendor advisory references, but lacks CVSS, CWE, exploit status, and detailed affected platform scope. Avoid assuming broader Mozilla products or active exploitation without additional cited evidence.
Mitigation direction
- Upgrade Firefox to version 53 or later.
- Upgrade Firefox ESR to version 52.1 or later.
- Check Mozilla and operating-system vendor advisories for supported fixed packages.
- Retire unsupported legacy Firefox builds from managed endpoints.
Validation and detection
- Inventory Firefox and Firefox ESR versions across endpoints.
- Flag Firefox below 53 and Firefox ESR below 52.1.
- Confirm patched packages through vendor package metadata where applicable.
- Review browser fleet controls for unsupported legacy versions.
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-2017-5456 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
- RHSA-2017:1106CVE reference · vendor-advisory, x_refsource_REDHAT
- https://www.mozilla.org/security/advisories/mfsa2017-12/CVE reference · x_refsource_CONFIRM
- https://bugzilla.mozilla.org/show_bug.cgi?id=1344415CVE reference · x_refsource_CONFIRM
- https://www.mozilla.org/security/advisories/mfsa2017-10/CVE 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.