Security readout for executives and security teams
Plain-English summary
CVE-2021-4340 is a critical SQL injection flaw in the uListing WordPress plugin through version 1.6.6. An unauthenticated attacker could manipulate the listing_id parameter to interfere with database queries and potentially extract sensitive site data.
Executive priority
Treat this as urgent for any public WordPress property using uListing. The vulnerability requires no login and could expose or alter database contents. If the plugin is not present, priority drops substantially.
Technical view
The issue is CWE-89 SQL injection caused by insufficient escaping and query preparation around user-supplied listing_id input. The CVSS 3.1 score is 9.8, reflecting network reachability, no authentication, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely limited to WordPress sites running the Directory Listings WordPress plugin uListing at version 1.6.6 or earlier. The provided affected-product metadata is sparse, so teams should verify installed plugin names and exact versions directly.
Exploitation context
The bundle does not show CISA KEV listing or other cited evidence of active exploitation. However, unauthenticated SQL injection in a WordPress plugin is a high-risk pattern because public-facing sites are reachable and database impact can be severe.
Researcher notes
Source evidence supports unauthenticated SQL injection through listing_id in uListing up to 1.6.6. No exploit code, confirmed exploitation, or CPE coverage is provided in the bundle. Validate exposure through asset inventory and version checks, not assumptions.
Mitigation direction
- Identify all WordPress sites using the uListing plugin.
- Update uListing beyond version 1.6.6 if a fixed release is available.
- If no trusted fix is available, disable or remove the plugin.
- Review vendor and plugin maintainers' current guidance before restoring use.
- Prioritize internet-facing production sites first.
Validation and detection
- Confirm the installed uListing version on each WordPress instance.
- Check plugin inventory across production, staging, and backups.
- Review web logs for unusual requests involving listing_id.
- Verify vulnerable plugin versions are no longer active after remediation.
- Confirm normal listing functionality after update or removal.
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-89: Database access and collection lookup
Injection into data stores can inform collection, data access, and exfiltration detection reviews. 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 lookupDatabase behavior lookup
The CVE wording references database injection or access, so collection and exfiltration review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-4340 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
- 9.8 (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:H
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:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
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.