Security readout for executives and security teams
Plain-English summary
Ruby applications using the ruby-mysql gem before 2.10.0 could disclose local client files when connecting to a malicious MySQL server. The main business risk is unintended exposure of secrets or sensitive files from systems that initiate database connections.
Executive priority
Prioritize remediation where Ruby applications handle sensitive files or secrets and connect to external or less-trusted MySQL infrastructure. Otherwise, treat as a targeted dependency update.
Technical view
The issue is a client-side file read in ruby-mysql: a malicious MySQL server can request local file content from a vulnerable client without explicit user authorization. The source bundle identifies ruby-mysql 2.9.14 and states the flaw is fixed in 2.10.0 and later.
Likely exposure
Exposure is likely limited to Ruby systems that use the ruby-mysql gem before 2.10.0 and connect to untrusted, attacker-controlled, or compromised MySQL servers.
Exploitation context
The supplied sources do not show CISA KEV listing or confirmed active exploitation. Practical exploitation requires influencing a vulnerable client to connect to a malicious or compromised MySQL server.
Researcher notes
Severity data is incomplete in the supplied bundle: no CVSS score is provided. Validate exposure by dependency version and database trust boundaries, not by internet-facing service scans alone.
Mitigation direction
- Upgrade ruby-mysql to version 2.10.0 or later.
- Inventory Ruby applications and dependencies for ruby-mysql usage.
- Avoid connecting vulnerable clients to untrusted MySQL servers.
- Review vendor and project guidance for any additional hardening steps.
Validation and detection
- Check dependency manifests and lockfiles for ruby-mysql versions before 2.10.0.
- Confirm deployed Ruby environments use ruby-mysql 2.10.0 or later.
- Identify applications connecting to third-party or unmanaged MySQL servers.
- Review logs and configuration for unexpected database endpoints.
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-610: 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 lookupCVE-2021-3779 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.rapid7.com/blog/post/2022/06/28/cve-2021-3779-ruby-mysql-gem-client-file-read-fixed/CVE 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.
Externally Controlled Reference to a Resource in Another Sphere
Externally Controlled Reference to a Resource in Another Sphere represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.