CVE-2026-73084: activepieces activepieces advisory

Advisory generated from the CVE record, CISA, Exploit Observer and VEDAS: what it is, whether it is exploited, who is affected, and how to fix and detect it.

What it is

Activepieces is an open source AI workflow automation platform. Prior to 0.83.0, the /api/redirect OAuth callback endpoint embeds the user-supplied code query parameter directly into an inline script block without proper escaping. A crafted request to /api/redirect with a malicious code value can break out of the script context and execute arbitrary JavaScript in the Activepieces origin when a logged-in user opens it. An unauthenticated attacker can access the victim’s session tokens or make authenticated API calls on the victim’s behalf. This issue is fixed in version 0.83.0.

Description quoted from the CVE record (assigned by GitHub_M, published 2026-08-11).

Weakness: CWE-79: Improper Neutralization of Input During Web Page Generation (‘Cross-site Scripting’); CWE-94: Improper Control of Generation of Code (‘Code Injection’)

How it can be exploited

Exploitable over the network with low attack complexity needing no privileges and a user must take an action. Impact: confidentiality low, integrity low, availability none. CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CISA assessment (SSVC): CISA has no evidence of exploitation. Automatable: no. Technical impact: partial.

Public exploit evidence (Exploit Observer)

Also known as: EUVD-2026-56552

VEDAS cluster: VEDAS:DAUNTLESSDINGO

Exploit Observer links 5 pieces of public exploit code or detection modules that name this CVE or one of its aliases.

Exploit code and modules (5)

Code that names this CVE. A repository can be a working exploit, a scanner, a fake or malware; read it before running anything.

Vulnerability databases and vendor advisories (2)

Catalogue entries, not exploit evidence.

Vulnerability database or vendor advisory: https://euvd.enisa.europa.eu/enisa/EUVD-2026-56552
Vulnerability database or vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2026-73084

1 more reference returned by Exploit Observer did not name this CVE or an alias, so they are left out.

VEDAS data as of 2026-11-01T17:12 UTC; fetched 2026-11-02.

Live scores

EPSS: 0.004
low predicted chance of attack
VEDAS: 0.985
strong exploit evidence
On CISA KEV: Not listed
Detection rule: Nuclei · Suricata

Who is affected

Product	Affected	Not affected
activepieces activepieces	version < 0.83.0	Not stated

Version ranges exactly as the CVE record states them. “Before X” means X is the first fixed version.

How to fix it

No fixed version or vendor advisory is listed in the CVE record yet. Watch the vendor’s security page.

How to detect it

Nuclei template (active check)

Activepieces - Reflected Cross-Site Scripting
Activepieces prior to 0.83.0 reflects the user-supplied “code” query parameter of the /redirect OAuth callback endpoint into an inline <script> block via JSON.stringify. JSON.stringify escapes quotes but does not neutralise a “</script>” sequence, so an unauthenticated attacker can supply a crafted code value that closes the script element early and injects arbitrary HTML/JavaScript which executes in the Activepieces origin when a victim opens the link.

Name and description quoted from the template, written by VEDAS.

The template sends 1 request (GET /redirect?code=vedasx%3C%2Fscript%3E%3Csvg%20onload%3Dalert(1)%3E); it decides using status, word matchers. Severity in the template: medium. Marked as not yet verified against a live vulnerable target.

Run it against a host you own or are authorised to test:

bash

nuclei -u https://your-host -t CVE-2026-73084.yaml

Show the template (44 lines)

yaml

id: CVE-2026-73084

info:
  name: "Activepieces - Reflected Cross-Site Scripting"
  author: vedas-arpsyndicate
  severity: medium
  description: |
    Activepieces prior to 0.83.0 reflects the user-supplied "code" query parameter of the /redirect
    OAuth callback endpoint into an inline <script> block via JSON.stringify. JSON.stringify escapes
    quotes but does not neutralise a "</script>" sequence, so an unauthenticated attacker can supply a
    crafted code value that closes the script element early and injects arbitrary HTML/JavaScript which
    executes in the Activepieces origin when a victim opens the link.
  reference:
    - https://www.exploit.observer/?keyword=CVE-2026-73084&match=exact
    - https://subdomain.center/?engine=ammonites&keyword=activepieces&match=exact
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 6.1
    cve-id: CVE-2026-73084
    cwe-id: CWE-79
  metadata:
    verified: false
    max-request: 1
  tags: cve,cve2026,activepieces,xss,unauth
http:
  - method: GET
    path:
      - "{{BaseURL}}/redirect?code=vedasx%3C%2Fscript%3E%3Csvg%20onload%3Dalert(1)%3E"

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "</script><svg onload=alert(1)>"

      - type: word
        part: header
        words:
          - "text/html"

      - type: status
        status:
          - 200

CVE-2026-73084.yaml on GitHub

Suricata rules (network detection)

1 rule that alert on traffic matching this exploit: VEDAS CVE-2026-73084 Activepieces - Reflected Cross-Site Scripting via /redirect code. Add them to your Suricata rule set and reload.

Show the rules

suricata

alert http $EXTERNAL_NET any -> $HTTP_SERVERS $HTTP_PORTS (msg:"VEDAS CVE-2026-73084 Activepieces - Reflected Cross-Site Scripting via /redirect code"; flow:established,to_server; http.uri; content:"/redirect?code="; nocase; fast_pattern; content:"script"; distance:0; nocase; content:"onload"; distance:0; nocase; classtype:web-application-attack; reference:cve,CVE-2026-73084; reference:url,https://www.exploit.observer/?keyword=CVE-2026-73084&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=activepieces&match=exact; sid:1099400; rev:1;)

CVE-2026-73084.rules on GitHub

References

Other references

https://github.com/activepieces/activepieces/security/advisories/GHSA-hc39-cm5m-q8g7 (x_refsource_CONFIRM)
https://github.com/activepieces/activepieces/commit/8be4c8d5e6a79ccbaa74815027432a3c8c311385 (x_refsource_MISC)
https://github.com/activepieces/activepieces/releases/tag/0.83.0 (x_refsource_MISC)

Other databases

Where this comes from

This advisory is generated automatically by VEDAS from: CVE.org record, cve-scores (EPSS and VEDAS), Exploit Observer, vedas-signatures. Text in quotes is reproduced from the source; everything else is a fixed template filled with source fields. Nothing here is written by a language model. Check the vendor advisory before acting, and read how VEDAS and Exploit Observer work, and their limits.