Security readout for executives and security teams
Plain-English summary
GestSup before 3.2.60 can store malicious content from an API request into error logs. If an administrator later opens those logs in the web interface, the content can run in the administrator’s browser. This is a moderate business risk because it depends on admin log viewing but can affect privileged sessions.
Executive priority
Prioritize remediation for internet-exposed GestSup systems and environments where administrators routinely inspect logs. The urgency is moderate: exploitation needs user interaction by an administrator, but the affected user is privileged and the vulnerable input is accepted through API error handling.
Technical view
CVE-2026-22198 is a stored XSS issue in GestSup API error logging. Sources describe crafted X-API-KEY header content being logged and later rendered without proper output encoding in the admin UI. The record lists CVSS 4.0 score 5.1 and CWE-79. The description says pre-authentication; the CVSS vector includes PR:L, so privilege requirements are inconsistent.
Likely exposure
Organizations running GestSup versions prior to 3.2.60 are potentially exposed, especially if the API is reachable and administrators review API error logs through the web interface. Public internet exposure of GestSup or its API would increase practical risk.
Exploitation context
The source bundle does not indicate known active exploitation, and KEV is false. Exploitation requires getting crafted content into API error logs and an administrator later viewing affected logs. This is not described as remote code execution, but it may compromise browser-session context or enable actions as the logged-in administrator.
Researcher notes
Primary evidence comes from the CVE record, GestSup changelog reference, and VulnCheck advisory. The affected range is described as prior to 3.2.60. No cited source in the bundle states active exploitation. Note the mismatch between the narrative’s pre-authentication wording and the CVSS PR:L vector.
Mitigation direction
- Upgrade GestSup to version 3.2.60 or later if applicable.
- Review GestSup changelog and vendor guidance for the official fix details.
- Restrict access to the GestSup API where operationally feasible.
- Treat suspicious API error log entries as potentially unsafe until patched.
Validation and detection
- Inventory deployed GestSup versions and identify any below 3.2.60.
- Confirm whether the API endpoint is reachable from untrusted networks.
- Review API error logs for unexpected HTML or script-like content.
- Verify administrators no longer render unsafe log content after remediation.
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 lookupCVE-2026-22198 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
- 5.1 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA: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:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
5.1MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- https://gestsup.fr/index.php?page=changelogCVE reference · release-notes
- https://www.vulncheck.com/advisories/gestsup-stored-xss-in-api-error-logsCVE reference · 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.