Security readout for executives and security teams
Plain-English summary
This issue is a stored cross-site scripting flaw in Delta Electronics DIAEnergie. An attacker could place malicious script content into a hierarchy description field, causing trusted users to load attacker-controlled code later. The provided CVSS score is medium, but integrity impact is high because stored content can affect normal application workflows.
Executive priority
Treat as a moderate-priority ICS application risk. Escalate if DIAEnergie is externally reachable, used by privileged operators, or integrated into operational reporting where stored content is routinely viewed.
Technical view
CVE-2021-31558 is CWE-79 in DIAEnergie 1.7.5 and prior. The source describes arbitrary code injection through the descr parameter of DIAE_hierarchyHandler.ashx. The description says unauthenticated injection, while the CVSS vector lists low privileges, so access requirements should be verified against vendor/CISA details.
Likely exposure
Exposure is likely limited to organizations running Delta Electronics DIAEnergie, especially if the application is reachable from business, facility, or remote access networks. The bundle names DIAEnergie 1.7.5 and prior; the affected entry also says all versions, which should be reconciled during inventory.
Exploitation context
The bundle does not show CISA KEV inclusion and provides no cited evidence of active exploitation. Stored XSS can still matter operationally because a single injected record may execute when legitimate users view affected application pages.
Researcher notes
The key uncertainty is access requirement: the narrative says unauthenticated, while CVSS uses PR:L. Do not assume exploitation in the wild from the provided evidence. Focus validation on affected version confirmation, reachable attack surface, and whether stored descriptions render unsafely.
Mitigation direction
- Check CISA and Delta guidance for fixed versions or vendor instructions.
- Inventory DIAEnergie deployments and identify versions 1.7.5 and prior.
- Restrict DIAEnergie access to trusted administrative networks.
- Remove or sanitize suspicious hierarchy description content.
- Prioritize upgrade or isolation for internet-reachable instances.
Validation and detection
- Confirm whether DIAEnergie is deployed and record its version.
- Review application logs for unexpected hierarchy description changes.
- Inspect affected fields for script-like or encoded content.
- Verify access controls around DIAE_hierarchyHandler.ashx.
- Retest after vendor remediation without using offensive payloads.
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-79: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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-2021-31558 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
- 6.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
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:L/UI:N/S:U/C:N/I:H/A:N2.83.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.5MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
Source materials
- CVE List V5 sourceCVE List V5
- https://www.cisa.gov/uscert/ics/advisories/icsa-21-238-03CVE reference · x_refsource_MISC
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 Input During Web Page Generation ('Cross-site Scripting')
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.