Security readout for executives and security teams
Plain-English summary
Proxyman for macOS 1.11.0 and earlier had a privileged helper tool issue that could let an attacker alter the system proxy. If abused, all traffic could be redirected through attacker-controlled infrastructure, creating a man-in-the-middle risk for affected Macs.
Executive priority
Treat this as a targeted workstation risk, not a confirmed internet-wide emergency. Prioritize developer and security testing Macs because proxy redirection can expose credentials, internal traffic, and session data.
Technical view
The issue is in com.proxyman.NSProxy.HelperTool, the privileged helper tool used by Proxyman for macOS. The CVE states it can allow system proxy changes that redirect all traffic to an attacker-controlled computer. The provided sources do not include CVSS, CWE, exploit prerequisites, or a confirmed fixed version.
Likely exposure
Exposure is limited to macOS systems running Proxyman 1.11.0 or earlier. This is most likely on developer, QA, or security testing workstations. The bundle does not identify affected macOS versions or remote exploitability.
Exploitation context
CISA KEV status is false, and the provided sources do not report active exploitation. The business concern is traffic interception if an attacker can abuse the helper tool to force proxy redirection.
Researcher notes
The public bundle is sparse. It identifies the vulnerable helper tool and impact, but not root cause, authentication boundary, attacker locality, CVSS, or patch version. Avoid assuming exploitability details beyond proxy redirection and MITM impact.
Mitigation direction
- Inventory macOS endpoints for Proxyman 1.11.0 or earlier.
- Check Proxyman vendor guidance for fixed versions or removal steps.
- Remove affected installations where Proxyman is not operationally required.
- Enforce expected system proxy settings through endpoint management.
- Monitor for unexpected proxy destination changes on developer workstations.
Validation and detection
- Confirm installed Proxyman versions across managed macOS endpoints.
- Check whether com.proxyman.NSProxy.HelperTool is present on affected hosts.
- Review endpoint telemetry for unexpected system proxy changes.
- Verify proxy settings match approved enterprise configuration.
- Confirm no affected Proxyman versions remain after remediation.
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-2019-20057 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://github.com/ProxymanApp/Proxyman/issues/364CVE reference · x_refsource_MISC
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.