Security readout for executives and security teams
Plain-English summary
CVE-2021-41691 is a critical SQL injection issue reported in OS4Ed openSIS Community v8.0. An unauthenticated network attacker may be able to affect student information confidentiality, integrity, and availability through vulnerable POST parameters. The supplied sources do not confirm active exploitation or a fixed release.
Executive priority
Treat as urgent where openSIS Community v8.0 protects student or school operational data. The rating supports rapid exposure confirmation and containment, but remediation planning should wait for verified vendor or project guidance if no maintained fix is available.
Technical view
The CVE describes CWE-89 SQL injection in /TransferredOutModal.php through student_id and TRANSFER{SCHOOL] POST parameters. CVSS 3.1 is 9.8 with network access, low complexity, no privileges, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely for internet- or intranet-accessible deployments of OS4Ed Open Source Information System Community/openSIS Community v8.0 that include /TransferredOutModal.php. The CVE metadata does not provide CPEs, vendor-normalized affected ranges, or hosting assumptions.
Exploitation context
The source bundle labels this as a 0-day report, but CISA KEV status is false and the supplied sources do not establish active exploitation. The vulnerability class is serious because SQL injection can expose or alter sensitive school records when reachable.
Researcher notes
Key gaps are affected-version normalization, patch status, and exploitation evidence. The CVE record provides parameter and endpoint names, but analysis should avoid assuming other openSIS editions or versions are affected without vendor confirmation.
Mitigation direction
- Check openSIS/OS4Ed project guidance for a fixed release or official workaround.
- Prioritize upgrade, replacement, or isolation of confirmed openSIS Community v8.0 deployments.
- Restrict access to affected administrative workflows until remediation guidance is confirmed.
- Increase monitoring for suspicious requests involving /TransferredOutModal.php.
- Confirm recent database backups and recovery procedures for affected environments.
Validation and detection
- Inventory openSIS Classic or Community deployments and confirm whether version 8.0 is present.
- Identify whether /TransferredOutModal.php is reachable from untrusted networks.
- Review web logs for unusual POST activity to /TransferredOutModal.php.
- Verify whether vendor or project documentation names a patched version.
- Document any compensating controls and residual exposure for school-data systems.
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-2021-41691 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
Source materials
- CVE List V5 sourceCVE List V5
- https://opensis.com/CVE reference
- https://github.com/OS4ED/openSIS-Classic/CVE reference
- https://resources.s4e.io/blog/opensis-student-information-system-0-day-vulnerability-cve-2021-41691/CVE reference
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.
Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection')
Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.