CVE-2021-42258
Published: 22 October 2021
Summary
CVE-2021-42258 is a critical-severity SQL Injection (CWE-89) vulnerability in Bqe Billquick Web Suite. Its CVSS base score is 9.8 (Critical).
Operationally, ranked in the top 0.1% of CVEs by exploit likelihood; CISA has added it to the Known Exploited Vulnerabilities catalog; a public proof-of-concept is referenced.
The strongest mitigations our analysis identified are NIST 800-53 SC-7 (Boundary Protection) and SI-10 (Information Input Validation).
Deeper analysis
BQE BillQuick Web Suite versions 2018 through 2021 before 22.0.9.1 contain a SQL injection vulnerability that permits unauthenticated remote code execution. The flaw is tracked as CWE-89 and carries a CVSS 3.1 score of 9.8. Exploitation can occur through parameters such as txtID, allowing an attacker to invoke xp_cmdshell and run arbitrary commands under the MSSQLSERVER$ account.
Unauthenticated remote attackers can leverage the injection to achieve code execution on the affected server. In practice this has enabled deployment of ransomware and other post-exploitation activity without any user interaction or authentication.
Public advisories from Huntress and CISA note that the issue was exploited in the wild in October 2021 and recommend upgrading to version 22.0.9.1 or later. The vulnerability is also listed in CISA's Known Exploited Vulnerabilities catalog, confirming active exploitation against internet-facing instances.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2021-29234
Vulnerability details
BQE BillQuick Web Suite 2018 through 2021 before 22.0.9.1 allows SQL injection for unauthenticated remote code execution, as exploited in the wild in October 2021 for ransomware installation. SQL injection can, for example, use the txtID (aka username) parameter. Successful…
more
exploitation can include the ability to execute arbitrary code as MSSQLSERVER$ via xp_cmdshell.
- CWE(s)
- KEV Date Added
- 03 November 2021
Related Threats
No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly requires validation of all inputs (e.g., txtID) to block SQL injection payloads before they reach the database.
Enforces boundary protection and deny-by-default rules that would have blocked unauthenticated external access to the vulnerable web application.
Mandates timely application of the vendor patch (v22.0.9.1) that eliminates the SQL injection flaw exploited for remote code execution.