CVE-2019-9874
CRITICALCVE-2019-9874 is a critical-severity (CVSS 9.8) Deserialization of Untrusted Data vulnerability. It is in CISA's Known Exploited Vulnerabilities catalog (added 2025-03-26) — treat it as actively exploited and patch now. No vendor fix is recorded yet; mitigation options are listed below.
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…
Exploitation Status
Actively exploited in the wild
- Confirmed by CISA's Known Exploited Vulnerabilities catalog on 2025-03-26. Federal agencies were required to remediate by 2025-04-16.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA (KEV catalog and SSVC triage) for CVE-2019-9874.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2019-9874 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).
Where this sits among everything scored
Of 394,803 CVEs with a current EPSS score, this one falls in the 50–90% band (highlighted). Counts from FIRST.org, log-scaled.
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.
Affected Products
cmssitecoreexperience platformsitecoreResearch use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
VulnerabilityDetect
Identify every host running the affected component and compare the installed build against the fixed version below — for source-built or distro-packaged software the version string, not a lockfile, is the source of truth (`dpkg -l`, `rpm -q`, or the binary's own `--version`).
Remediation status
No fixed release is recorded for CVE-2019-9874 yet. Track the upstream advisory, and apply the exposure-reduction steps below in the meantime.
Mitigate without a patch
Do not deserialise data from untrusted sources: where the format allows it, restrict deserialisation to an explicit allowlist of expected types, and prefer a data-only format (JSON, Protobuf) over one that can reconstruct arbitrary objects until you can upgrade.
How to detect CVE-2019-9874
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id cve-2019-9874 -u https://target- Template
- Sitecore Experience Platform - Deserialization of Untrusted Data
- Severity
- critical
- Impact
- Attackers can execute arbitrary code remotely, potentially leading to full system compromise.
- Remediation
- Update to the latest version of Sitecore or apply security patches addressing deserialization issues.
Template by ProjectDiscovery nuclei-templates (ritikchaddha), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is CVE-2019-9874 in your dependencies?
Find it across , including transitive dependencies.