CVE-2016-4437

CRITICALNVD 9.89.8—Trending — 4 sources updated this weekExploited in the wild

9.8

Apache Shiro before 1.2.5, when a cipher key has not been configured for the "remember me" feature, allows remote attackers to execute arbitrary code or bypass intended access restrictions via an unspecified request parameter.

CVSS v3: 9.8
EG Score: 9.8(medium)
EPSS: 99.9%
KEV: ⚠ Exploited

Published

June 7, 2016

Last Modified

April 22, 2026

Advisory Details (5)

Auto-updated May 12, 2026

No patch confirmed yet.

generic

http://rhn.redhat.com/errata/RHSA-2016-2035.html

generic

https://lists.apache.org/thread.html/ef3a800c7d727a00e04b78e2f06c5cd8960f09ca28c9b69d94c3c4c4%40%3Cannouncements.aurora.apache.org%3E

generic

http://www.securityfocus.com/bid/91024

generic

http://www.securityfocus.com/archive/1/538570/100/0/threaded

generic

http://rhn.redhat.com/errata/RHSA-2016-2036.html

Patch Availability(3)

Vendor / Ecosystem	Fixed in / Patch	Released	Source
ubuntu	libshiro-java (1.2.4-1ubuntu0.1~esm1) @ xenial	2026-06-03	ubuntu
redhat	patch	2016-10-06	redhat
redhat	patch	2016-10-06	redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)

Maven(1)

Package	Vulnerable range	Fixed in	Dependents
org.apache.shiro:shiro-core	1.0.0-incubating ... 1.2.4 (7 versions)	1.2.5	—

All Vendor Advisories

(3)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 20× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-03 19:09 UTCkev_newly_listed
2026-06-03 17:26 UTCEG score recompute
2026-06-03 17:26 UTCVendor advisory
2026-06-03 13:06 UTCEG score recompute
2026-06-03 13:06 UTCVendor advisory
2026-06-03 08:46 UTCEG score recompute
2026-06-03 08:46 UTCVendor advisory
2026-06-03 04:26 UTCEG score recompute
2026-06-03 04:26 UTCVendor advisory
2026-06-03 00:06 UTCEG score recompute
2026-06-03 00:06 UTCVendor advisory
2026-06-02 19:46 UTCEG score recompute
2026-06-02 19:46 UTCVendor advisory
2026-06-02 18:32 UTCkev_newly_listed
2026-06-02 15:26 UTCEG score recompute
2026-06-02 15:26 UTCVendor advisory
2026-06-02 11:06 UTCEG score recompute
2026-06-02 11:06 UTCVendor advisory
2026-06-02 06:46 UTCEG score recompute
2026-06-02 06:46 UTCVendor advisory

Publicly available exploits

(6 references)

Working exploit code is in the public domain (1 Metasploit module) (3 GitHub PoCs) (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

GitHub PoCpizza-power/CVE-2016-4437
First seen Dec 22, 2023
Python POC to Exploit CVE-2016-4437 Apache Shiro Deserialization Vulnerability Due to Hardcode Encryption Key
Open source ↗
GitHub PoC4nth0ny1130/shisoserial
First seen Dec 23, 2021
一个针对shiro反序列化漏洞(CVE-2016-4437)的快速利用工具/A simple tool targeted at shiro framework attacks with ysoserial.
Open source ↗
GitHub PoCbkfish/Awesome_shiro
First seen May 27, 2020
CVE-2016-4437-Shiro反序列化爆破模块和key,命令执行，反弹shell的脚本
Open source ↗
Exploit-DBEDB-48410✓ verified
First seen May 1, 2020
Apache Shiro 1.2.4 - Cookie RememberME Deserial RCE (Metasploit)
Open source ↗
Metasploitexploit/multi/http/shiro_rememberme_v124_deserialize✓ verified
First seen Jun 7, 2016
Apache Shiro v1.2.4 Cookie RememberME Deserial RCE
Open source ↗
Nucleihttp/cves/2016/CVE-2016-4437.yaml
First seen Jan 1, 2016
Apache Shiro 1.2.4 Cookie RememberME - Deserial Remote Code Execution Vulnerability
Open source ↗

Frequently asked(6)

What is CVE-2016-4437?

CVE-2016-4437 is a critical vulnerability published on June 7, 2016. Apache Shiro before 1.2.5, when a cipher key has not been configured for the "remember me" feature, allows remote attackers to execute arbitrary code or bypass intended access restrictions via an unspecified request parameter.

When was CVE-2016-4437 disclosed?

CVE-2016-4437 was first published in the National Vulnerability Database on June 7, 2016, with the most recent update on April 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2016-4437 actively exploited?

Yes. CISA added CVE-2016-4437 to the Known Exploited Vulnerabilities catalog on November 3, 2021, affecting Apache Shiro. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.

What is the CVSS score of CVE-2016-4437?

CVE-2016-4437 has a CVSS v3 base score of 9.8 (NVD).

Which products are affected by CVE-2016-4437?

CVE-2016-4437 affects Apache Shiro. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.

How do I remediate CVE-2016-4437?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2016-4437, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2016-4437

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CVE-2016-4437

📅 Published

🔄 Last Modified

📋 Advisory Details (5)

Patch Availability(3)

Affected Packages

All Vendor Advisories

Data Freshness Timeline

Publicly available exploits

❓ Frequently asked(6)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2016-4437?

🔗 Related CVEs(same vendor)

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Published

Last Modified

Advisory Details (5)

Frequently asked(6)

Related CVEs(same vendor)