Security readout for executives and security teams
Plain-English summary
Adminer versions before 5.4.3 can let an unauthenticated remote attacker turn a crafted database server value into code written on the web server. Accessing that file can then execute the code, potentially exposing data, altering systems, or disrupting service.
Executive priority
Treat exposed instances as an immediate remediation priority. Upgrade to 5.4.3 or later, restrict access, and investigate for compromise. Internal-only deployments still require prompt validation because exploitation needs neither credentials nor user interaction when the vulnerable interface is reachable.
Technical view
Adminer insufficiently sanitizes the MSSQL server field before building a PDO DSN. Semicolon injection permits attacker-controlled ODBC parameters, including TraceFile and TraceOn. These parameters can write PHP into the web root; requesting the resulting file produces remote code execution without authentication or user interaction.
Likely exposure
Exposure is highest where Adminer before 5.4.3 is reachable from untrusted networks and its MSSQL PDO/ODBC path is available. The supplied sources do not establish how common those conditions are. Internet-accessible instances should be treated as urgent until version and configuration are verified.
Exploitation context
The CVSS 3.1 score is 9.8, reflecting network access, low complexity, no privileges, and complete confidentiality, integrity, and availability impact. The bundle marks KEV as false and provides no cited evidence of active exploitation. That absence does not establish that exploitation is not occurring.
Researcher notes
The issue is classified as CWE-73 and concerns attacker-controlled file naming or paths through injected ODBC tracing parameters. The supplied evidence identifies the vulnerable construction and code-execution outcome but does not document observed exploitation, prevalence, detection signatures, or every required environmental condition.
Mitigation direction
- Upgrade Adminer to version 5.4.3 or later.
- Restrict Adminer access to trusted administrators and management networks.
- Follow the vendor advisory for any additional deployment-specific guidance.
- Review web-root files and server activity for possible compromise before returning service.
Validation and detection
- Inventory all deployed Adminer instances and record their exact versions.
- Confirm no instance older than 5.4.3 is reachable from untrusted networks.
- Verify the upgraded version through deployment records and the running application.
- Inspect web roots for unexpected PHP files or recently created trace artifacts.
- Review relevant web and application logs for suspicious unauthenticated connection attempts.
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-73: File access and web shell behavior lookup
File traversal and upload weaknesses can lead teams to review file, web shell, execution, and collection telemetry. 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 lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-56705 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.
SSVC decision data
CVSS vector scores
2 official scoresWe 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:H3.95.9VulnCheckCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N——VulnCheckVulnerability scoring details
Base CVSS 4.0 score
9.3CriticalVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
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
Vulnerability timeline
Timeline events are normalized from CVE metadata, CNA source timelines, ADP timelines, and KEV metadata when present.
- CVE reservedCVE Program
The CVE ID was reserved by the assigning CNA.
- CVE publishedCVE Program
The CVE record was published.
- CVE updatedCVE Program
The CVE record metadata indicates this as the latest update time.
ADP provider summaries
Source materials
- CVE List V5 sourceCVE List V5
- GitHub Security Advisory (GHSA-r4x9-5m63-3vxw)CVE reference, VulnCheck · vendor-advisory
- VulnCheck Advisory: Adminer before 5.4.3 Remote Code Execution via MSSQL PDO DSN InjectionCVE reference, VulnCheck · third-party-advisory
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.
External Control of File Name or Path
External Control of File Name or Path represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.