CVE-2019-9874: Sitecore exploited

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

Deserialization of Untrusted Data in the Sitecore.Security.AntiCSRF (aka anti CSRF) module in Sitecore CMS 7.0 to 7.2 and Sitecore XP 7.5 to 8.2 allows an unauthenticated attacker to execute arbitrary code by sending a serialized .NET object in the HTTP POST parameter __CSRFTOKEN.

Description quoted from the CVE record (assigned by mitre, published 2019-05-31).

Weakness: CWE-502 Deserialization of Untrusted Data

How it can be exploited

Exploitable over the network with low attack complexity needing no privileges and no user interaction. Impact: confidentiality high, integrity high, availability high. CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

CISA assessment (SSVC): CISA assesses exploitation as active. Automatable: yes. Technical impact: total.

On CISA KEV since: 2025-03-26
US federal deadline: 2025-04-16
Ransomware use: Not known

Public exploit evidence (Exploit Observer)

Also known as: BDU:2025-14503, CNNVD-201905-1224, EUVD-2019-19230, GHSA-wfwm-vf76-3692

VEDAS cluster: VEDAS:FACETEDGEM

Exploit Observer links 6 pieces of public exploit code or detection modules that name this CVE or one of its aliases.

Exploit code and modules (6)

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 (5)

Catalogue entries, not exploit evidence.

Vulnerability database or vendor advisory: https://euvd.enisa.europa.eu/enisa/EUVD-2019-19230
Vulnerability database or vendor advisory: https://github.com/advisories/GHSA-wfwm-vf76-3692
Vulnerability database or vendor advisory: https://nvd.nist.gov/vuln/detail/CVE-2019-9874
Vulnerability database or vendor advisory: https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-9874
Vulnerability database or vendor advisory: https://www.cnnvd.org.cn/home/globalSearch?keyword=CNNVD-201905-1224

23 more references 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: 0.837
very likely to be attacked soon
VEDAS: 0.984
strong exploit evidence
On CISA KEV: Yes, since 2025-03-26
Detection rule: Nuclei · Suricata

EPSS (chance of attack)

VEDAS (exploit evidence)

Thin horizontal line: the “likely” (EPSS 0.10) or “strong” (VEDAS 0.90) threshold. Shaded “no data” areas are periods when cve-scores did not publish.

Who is affected

Product	Affected	Not affected
Not stated	version n/a	Not stated

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

How to fix it

CISA required action: Apply mitigations per vendor instructions, follow applicable BOD 22-01 guidance for cloud services, or discontinue use of the product if mitigations are unavailable.

Vendor guidance:

How to detect it

Nuclei template (active check)

Sitecore.Security.AntiCSRF - Insecure Deserialization
Deserialization of Untrusted Data in the Sitecore.Security.AntiCSRF (aka anti CSRF) module in Sitecore CMS 7.0 to 7.2 and Sitecore XP 7.5 to 8.2 allows an unauthenticated attacker to execute arbitrary code by sending a serialized .NET object in the HTTP POST parameter __CSRFTOKEN.

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

The template sends 1 request (POST /sitecore/shell/Applications/Security/CreateNewUser/CreateNewUser.aspx); it confirms through an out-of-band callback (interactsh), so the scanner must be able to receive it; it decides using status, word matchers. Severity in the template: critical. 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-2019-9874.yaml

Show the template (44 lines)

yaml

id: CVE-2019-9874

info:
  name: "Sitecore.Security.AntiCSRF - Insecure Deserialization"
  author: vedas-arpsyndicate
  severity: critical
  description: |
    Deserialization of Untrusted Data in the Sitecore.Security.AntiCSRF (aka anti CSRF) module in Sitecore CMS 7.0
    to 7.2 and Sitecore XP 7.5 to 8.2 allows an unauthenticated attacker to execute arbitrary code by sending a
    serialized .NET object in the HTTP POST parameter __CSRFTOKEN.
  reference:
    - https://www.exploit.observer/?keyword=CVE-2019-9874&match=exact
    - https://subdomain.center/?engine=ammonites&keyword=sitecore&match=exact
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
    cvss-score: 9.8
    cve-id: CVE-2019-9874
    cwe-id: CWE-502
  metadata:
    verified: false
  tags: cve,cve2019,sitecore,deserialization,rce,kev,vkev,vuln
http:
  - raw:
      - |
        POST /sitecore/shell/Applications/Security/CreateNewUser/CreateNewUser.aspx HTTP/1.1
        Host: {{Hostname}}
        Content-Type: application/x-www-form-urlencoded
        Cookie: __CSRFCOOKIE={{randstr}};

        __CSRFTOKEN={{generate_java_gadget("dns", "https://{{interactsh-url}}", "base64")}}

    matchers-condition: and
    matchers:
      - type: word
        part: body
        words:
          - "PotentialCsrfException"
          - "deserialization"
        condition: and
        case-insensitive: true

      - type: status
        status:
          - 500

CVE-2019-9874.yaml on GitHub

Suricata rules (network detection)

1 rule that alert on traffic matching this exploit: VEDAS CVE-2019-9874 Sitecore.Security.AntiCSRF - Insecure Deserialization. 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-2019-9874 Sitecore.Security.AntiCSRF - Insecure Deserialization"; flow:established,to_server; http.uri; content:"CreateNewUser.aspx"; nocase; http.request_body; content:"https://"; nocase; fast_pattern; classtype:web-application-attack; reference:cve,CVE-2019-9874; reference:url,https://www.exploit.observer/?keyword=CVE-2019-9874&match=exact; reference:url,https://subdomain.center/?engine=ammonites&keyword=sitecore&match=exact; sid:1010489; rev:1;)

CVE-2019-9874.rules on GitHub

References

Government sources

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2019-9874 (government-resource)

Other references

https://dev.sitecore.net/Downloads.aspx (x_refsource_MISC)
https://www.synacktiv.com/blog.html (x_refsource_MISC)
https://www.synacktiv.com/ressources/advisories/Sitecore_CSRF_deserialize_RCE.pdf (x_refsource_MISC)

Other databases

Where this comes from

This advisory is generated automatically by VEDAS from: CVE.org record, CISA KEV, 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.