ZeroDay Findings
Sign inSign up

Findings

Vulnerability · CVE-2026-16723

alibaba fastjson Improper Input Validation

Published Jul 23, 2026 · corrected/updated Jul 23, 2026 · alibaba fastjson · evidence confidence very high

A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83. This vulnerability is exploitable under fastjson's stock default configuration — no AutoType enablement required, no classpath gadget required. Initial-access exploit intelligence.

Grounded briefings

Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.

Executive

CVE-2026-16723 is a unknown public vulnerability record for alibaba fastjson. CISA lists it as known exploited. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.

System administrator

Identify whether alibaba fastjson is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: alibaba fastjson. Published remediation guidance: Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.

Security analyst

Signals on file: EPSS 0.7%. CISA lists it as known exploited. Sources contributing to this record: cve_org, epss, vulncheck_kev. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.

Exploitation and remediation

  • Exploitation evidence

    Confirmed in CISA KEV since Jul 23, 2026. Listed in CISA KEV and VulnCheck KEV.

  • Patch and remediation

    Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

  • Safe detection guidance

    Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.

Code

The project this record applies to. Exploit listings stay in References.

No public source repository is identified for this product.

Timeline

Detection, updates, and resolution for this record.

  1. Jul 23, 2026 · VulnCheck KEV

    Detected

    A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83. This vulnerability is exploitable under fastjson's stock default configuration — no AutoType enablement required, no classpath gadget required. Initial-access exploit intelligence.

  2. Jul 23, 2026 · CISA KEV

    Known exploited

    Apply remediations or mitigations per vendor instructions or discontinue use of the product if remediation or mitigations are unavailable.

Affected

  • vendor alibaba fastjsonversion unspecified

Sources

  • CVE.orgVulnerability recordCVE-2026-16723

    Official CVE identifier

    cve.org
  • FIRST EPSSExploitation probabilityCVE-2026-16723

    30-day exploitation probability 0.7%

    first.org
  • VulnCheck KEVConfirmed exploitationCVE-2026-16723

    A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83. This vulnerability is exploitable under fastjson's stock default configuration — no AutoType enablement required, no classpath gadget required.

    vulncheck.com

References