Security readout for executives and security teams
Plain-English summary
A flaw in Fortinet's FortiDeceptor deception platform lets a signed-in administrator with only read-only rights read log files they should not necessarily see by sending specially crafted web requests. The impact is limited to information disclosure from logs, and an attacker must already have valid admin credentials, so the practical risk is contained but real for anyone managing multi-tenant or least-privilege admin roles.
Executive priority
Moderate priority. Business impact is limited to log data disclosure and requires an existing admin login, so this is not an emergency. Schedule the Fortinet-provided update in the next regular maintenance window and confirm least-privilege on FortiDeceptor admin roles.
Technical view
CVE-2026-25690 is an argument injection weakness (CWE-88) in FortiDeceptor 5.0 through 6.0.2. Insufficient neutralization of argument delimiters in an HTTP-driven command lets an authenticated admin — including read-only roles — inject arguments that cause the backend to disclose log file contents. CVSS 3.1 base is 4.0 (AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N) with confidentiality-only impact; the temporal vector notes a functional exploit and an official fix.
Likely exposure
FortiDeceptor appliances (versions 5.0.x, 5.1.x, 5.2.0–5.2.1, 5.3.0–5.3.3, and 6.0.0–6.0.2) whose management interface is reachable by any admin account, including read-only operators, auditors, or delegated tenants. Exposure grows where admin UI access is broad or credentials are shared.
Exploitation context
Not listed in CISA KEV and no public reports of in-the-wild abuse are cited in the bundle. The CVSS temporal string indicates a functional exploit exists and an official remediation is available. Attack requires prior authentication with at least read-only admin rights, which limits opportunistic use but raises insider and post-compromise concerns.
Researcher notes
CWE-88 argument injection in an authenticated HTTP handler suggests a delimiter (space, quote, or shell metacharacter) is passed into a log-reading command without adequate sanitization. Scope is Unchanged and only confidentiality is affected, aligning with read-only log exfiltration rather than command execution. Validate whether the flaw allows path traversal into logs outside the intended scope, and whether audit logging captures the abused requests. No public PoC is cited in the bundle.
Mitigation direction
- Consult Fortinet PSIRT advisory FG-IR-26-138 and upgrade FortiDeceptor to the vendor-fixed release for your branch.
- Restrict management interface reachability to trusted admin networks and jump hosts.
- Audit and prune read-only and low-privilege admin accounts; enforce MFA on all admin logins.
- Rotate credentials for any shared or service admin accounts on affected appliances.
- If patching is delayed, monitor admin activity closely and treat read-only accounts as sensitive.
Validation and detection
- Confirm running FortiDeceptor version via the appliance UI or CLI against the affected list (5.0–6.0.2).
- Cross-check the deployed build against the fixed version stated in Fortinet advisory FG-IR-26-138.
- Review admin role assignments, especially read-only accounts, and their recent login and API activity.
- Inspect HTTP management logs for unusual parameter patterns targeting log-retrieval endpoints by admin users.
- After upgrading, retest with a low-privilege admin account to confirm log endpoints no longer expose unintended data.
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-88: Command execution behavior lookup
Command injection weaknesses can lead defenders to review execution techniques and command interpreter 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 lookupCVE-2026-25690 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
- Medium
- CVSS
- 4 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:F/RL:O/RC:C
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
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:L/UI:N/S:U/C:L/I:N/A:N/E:F/RL:O/RC:C2.81.4fortinetVulnerability scoring details
Base CVSS 3.1 score
4MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:F/RL:O/RC:C
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
- https://fortiguard.fortinet.com/psirt/FG-IR-26-138CVE reference, fortinet
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 Argument Delimiters in a Command ('Argument Injection')
Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.