Security readout for executives and security teams
Plain-English summary
A Brother MFC-J491DW device web login can leak a password-derived MD5 value before authentication. An attacker who can reach the printer interface may crack the password offline and then administer the device.
Executive priority
Treat this as urgent where affected printer administration interfaces are network-accessible. The issue can expose administrator credentials without login, but vendor fix details are incomplete in the provided sources.
Technical view
Failed web-interface login responses return an incomplete authorization cookie containing the hexadecimal MD5 hash of the password. CVSS 3.1 is 9.1: network exploitable, low complexity, no privileges, no user interaction, with high confidentiality and integrity impact.
Likely exposure
Exposure is limited to reachable Brother MFC-J491DW C1806180757 printer web interfaces. Internet-facing or broadly reachable internal management interfaces carry the highest business risk.
Exploitation context
The provided sources do not show CISA KEV listing or confirmed active exploitation. Public disclosure exists, and the CVE description explains offline password cracking from the leaked hash.
Researcher notes
The CVE maps to CWE-276, though the observed failure is unauthenticated disclosure of a password hash through login response headers. The source bundle lacks CPEs, fixed versions, patch identifiers, and confirmed exploitation evidence.
Mitigation direction
- Check Brother security guidance for firmware, advisories, or model-specific remediation.
- Remove printer administration interfaces from internet-facing access.
- Restrict web management to trusted admin networks or VPN access.
- Use strong unique administrator passwords after remediation guidance is applied.
- Inventory Brother MFC-J491DW C1806180757 devices and prioritize remediation.
Validation and detection
- Identify Brother MFC-J491DW C1806180757 devices in asset inventory.
- Confirm web management is reachable only from trusted management networks.
- Review Brother support advisories for firmware or remediation status.
- Check device administration logs for unexpected access or configuration changes.
- Document any affected devices lacking vendor-confirmed fixes.
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.
CWE-276: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2019-20457 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
- Critical
- CVSS
- 9.1 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
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 vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N3.95.2Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.1CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://global.brother/CVE reference
- https://support.brother.com/g/s/security/en/index.htmlCVE reference
- 20240729 Bunch of IoT CVEsCVE reference · mailing-list
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.
Incorrect Default Permissions
Incorrect Default Permissions represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.