Deserialization in VMware Spring Security
CVE-2017-4995
An issue was discovered in Pivotal Spring Security 4.2.0.RELEASE through 4.2.2.RELEASE, and Spring Security 5.0.0.M1. When configured to enable default typing, Jackson contained a deserialization vulnerability that could lead to arbitrary code execution. Jackson fixed this vulnerability by blacklisting known "deserialization gadgets." Spring Security configures Jackson with global default typing enabled, which means that (through the previous exploit) arbitrary code could be executed if all of the following is true: (1) Spring Security's Jackson support is being leveraged by invoking SecurityJackson2Modules.getModules(ClassLoader) or SecurityJackson2Modules.enableDefaultTyping(ObjectMapper); (2) Jackson is used to deserialize data that is not trusted (Spring Security does not perform deserialization using Jackson, so this is an explicit choice of the user); and (3) there is an unknown (Jackson is not blacklisting it already) "deserialization gadget" that allows code execution present on the classpath. Jackson provides a blacklisting approach to protecting against this type of attack, but Spring Security should be proactive against blocking unknown "deserialization gadgets" when Spring Security enables default typing.
Vulnerability class: Insecure Deserialization
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.1 (High). Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.025 (84.5th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 85th percentile — 84.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.025 · newest: 0.025 · change: 0.000
Affected products
- VMware Spring Security — versions 4.2.0, 4.2.1, 4.2.2
- Spring Security 4.2.0.release 4.2.2.release And 5.0.0.m1 — versions Spring Security Spring Security 4.2.0.RELEASE 4.2.2.RELEASE and Spring Security 5.0.0.M1
Weakness classification (CWE)
Public proof-of-concept exploits
References
- pivotal.io/security/cve-2017-4995 (Issue Tracking, Vendor Advisory)
- www.securityfocus.com/bid/99080 (vdb-entry, Broken Link)
- lists.apache.org/thread.html/4641ed8616ccc2c1fbddac2c3dc9900c96387bc226eaf0232d… (mailing-list)
- lists.apache.org/thread.html/rf7f87810c38dc9abf9f93989f76008f504cbf7c1a35521464… (mailing-list)
- lists.apache.org/thread.html/r42ac3e39e6265db12d9fc6ae1cd4b5fea7aed9830dc6f6d58… (mailing-list)
Frequently asked questions
- What is CVE-2017-4995?
- CVE-2017-4995 is a high-severity vulnerability in VMware Spring Security, classified under Deserialization of Untrusted Data. CVSS score: 8.1/10. Published 2017-11-27.
- How severe is CVE-2017-4995?
- High severity. CVSS v3 base score is 8.1 out of 10.
- Is CVE-2017-4995 known to be exploited?
- 3 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.