Security readout for executives and security teams
Plain-English summary
HeyForm versions before 3.0.0-rc.7 allow a low-privileged team member to place malicious script in a form field title. If a team owner views the form, the script can run with the owner’s privileges, potentially enabling complete account takeover.
Executive priority
Prioritize an expedited upgrade because successful exploitation could convert limited team access into owner-level account control. Immediate emergency response is most warranted where affected versions are internet-accessible and team membership is broadly delegated. There is no supplied evidence of active exploitation.
Technical view
This is stored cross-site scripting (CWE-79) in HeyForm’s handling of form field titles. Exploitation is network-accessible and low-complexity but requires team membership and owner interaction. The CVSS 3.1 score is 9.0, reflecting potential high confidentiality, integrity, and availability impact across a changed security scope.
Likely exposure
Deployments running HeyForm versions earlier than 3.0.0-rc.7 are affected. Risk is greatest where untrusted or less-trusted team members can modify forms subsequently viewed by owners. The supplied sources do not establish how many public deployments are exposed.
Exploitation context
The vulnerability supports privilege escalation from a low-privileged team member to a team owner through stored script execution. CISA KEV status is false, and the supplied evidence does not confirm active exploitation in the wild. Treat exploitation status as unknown rather than absent.
Researcher notes
The assigned weakness is CWE-79, with CVSS vector CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H. The advisory identifies field titles as the storage point, owner viewing as the trigger, and 3.0.0-rc.7 as patched. A patch commit is public, but this assessment does not infer additional vulnerable sinks or affected branches.
Mitigation direction
- Upgrade HeyForm to version 3.0.0-rc.7 or later.
- Until upgraded, restrict form-editing access to trusted team members.
- Review vendor guidance and the referenced patch before applying compensating controls.
- If compromise is suspected, invalidate affected owner sessions and review privileged account activity.
Validation and detection
- Identify every HeyForm deployment and record its exact running version.
- Confirm each deployment runs version 3.0.0-rc.7 or later.
- Review available audit records for unexpected field-title changes and owner activity.
- Verify low-privileged users cannot retain unnecessary form-editing permissions.
- Test the patched application using harmless input that cannot execute script.
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 lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-35198 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 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/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
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:R/S:C/C:H/I:H/A:H2.36GitHub_MVulnerability scoring details
Base CVSS 3.1 score
9CriticalVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/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
- https://github.com/heyform/heyform/security/advisories/GHSA-chmm-jqpm-3pwxCVE reference, GitHub_M · x_refsource_CONFIRM
- https://github.com/heyform/heyform/commit/cc97d27a57ae400fec23abf5dcf6f9533c3b5db3CVE reference, GitHub_M · x_refsource_MISC
- https://vokecyber.com/research/cve-2026-35198-heyform-stored-xssCVE reference, GitHub_M · 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.