CVE-2026-16723Fastjson Insecure Deserialization
A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83.
Published Jul 23, 2026 · Updated Sep 10, 2026 · Also known as EUVD-2026-47929, GHSA-crf3-v9rr-v7hj
Key Facts
Patch immediately- CVE-2026-16723 is a critical-severity vulnerability (CVSS 9.0 v3.1) affecting seata (chainguard), com.alibaba:fastjson (maven), Fastjson.
- It is exploited in the wild, listed in CIRCL KEV, Industry KEV feed since Jul 23, 2026. No public exploit code is known.
- EPSS estimates a 0.7% probability of exploitation in the next 30 days.
- Fixed versions are available, including seata 2.7.0-r4.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Scores
CVSS v3.1
9.0
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
0.7%
Higher than 51.1% of all scored CVEs
Exploit maturity
Exploited (KEV)
ATLAS score
65/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Jul 23, 2026
0 days after publication
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Exploited (KEV)
Public exploit code
10
Proof-of-concept links
In-the-wild evidence
5
Reports of active use
Advisories And Exploit References
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2026-16723
- advisoryGHSA advisory
Description
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.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| CIRCL KEV | Jul 23, 2026 | n/a | Not reported |
| Industry KEV feed | Jul 23, 2026 | n/a | Not reported |
Affected Products
4 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| seatachainguard | See advisory | 2.7.0-r4 |
| com.alibaba:fastjsonmaven | >= 1.2.68 | n/a |
| Fastjson | >= 1.2.68 | n/a |
Patched Releases
seata
2.7.0-r4
Timeline
Publicly disclosed
Jul 23, 2026
Added to CIRCL KEV
Jul 23, 2026
Added to Industry KEV feed
Jul 23, 2026
Last updated
Sep 10, 2026
Weakness Type
- CWE-20 Improper Input Validation
- CWE-502 Deserialization of Untrusted Data
References
- advisorynvd.nist.gov · CVE-2026-16723
- advisoryGHSA advisory
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
- exploitVulnCheck exploitation report
FAQ
Common Questions.
A remote code execution (RCE) vulnerability exists in fastjson 1.2.68 through 1.2.83.
Affected: seata (chainguard); com.alibaba:fastjson (maven) versions >= 1.2.68; Fastjson versions >= 1.2.68. The full list is in the CVE brief.
It is exploited in the wild, listed in CIRCL KEV, Industry KEV feed since Jul 23, 2026.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including seata 2.7.0-r4.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Is CVE-2026-16723 On Your Attack Surface?
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