Security readout for executives and security teams
Plain-English summary
This is a critical unsafe deserialization issue in Clojure before 1.9.0. If an application accepts untrusted serialized Java objects, crafted data could make the server run attacker-controlled code. Business risk is highest for Java/Clojure services or vendor products that deserialize data from users, integrations, queues, or files.
Executive priority
Treat as urgent when Clojure before 1.9.0 exists in systems that deserialize external data. If the organization only uses newer Clojure or does not deserialize untrusted objects, urgency drops, but inventory should still be completed quickly.
Technical view
CVE-2017-20189 is CWE-502 unsafe deserialization affecting Clojure before 1.9.0. The source description says Clojure classes can construct a serialized object that executes arbitrary code during deserialization, when a server deserializes untrusted objects. CVSS 3.1 is 9.8: network exploitable, low complexity, no privileges, no user interaction.
Likely exposure
Exposure depends on two conditions: Clojure before 1.9.0 and a code path that deserializes untrusted Java objects. The source bundle does not identify specific affected applications beyond Clojure or NetApp advisory coverage.
Exploitation context
The CVE is not listed as KEV in the supplied data, so active exploitation is not confirmed here. Public references include research and ysoserial-related material, indicating known exploit concepts, but this analysis should not be treated as evidence of current attacks.
Researcher notes
The affected field in the bundle is incomplete, but the CVE description, Clojure issue, commit reference, and Snyk advisory point to Clojure before 1.9.0. Avoid assuming exposure without proving the unsafe deserialization path.
Mitigation direction
- Upgrade Clojure dependencies to 1.9.0 or later where applicable.
- Block deserialization of untrusted Java objects in exposed services.
- Review vendor advisories for products that may embed vulnerable Clojure versions.
- Use dependency scanning to flag org.clojure/clojure versions before 1.9.0.
- Prioritize internet-facing services and integration endpoints first.
Validation and detection
- Generate an SBOM and identify Clojure dependency versions.
- Search application code for Java object deserialization paths.
- Confirm whether any deserialization accepts user-controlled or partner-controlled input.
- Check NetApp advisory applicability for deployed NetApp products.
- Retest dependency scanners after upgrade or vendor remediation.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-502: Code execution behavior lookup
Code execution and unsafe deserialization weaknesses often justify reviewing execution behavior and process telemetry. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupExecution behavior lookup
The CVE wording references code or command execution, so execution technique review may help defensive triage. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2017-20189 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://hackmd.io/%40fe1w0/HyefvRQKpCVE reference
- https://clojure.atlassian.net/browse/CLJ-2204CVE reference
- https://github.com/frohoff/ysoserial/pull/68/filesCVE reference
- https://github.com/clojure/clojure/commit/271674c9b484d798484d134a5ac40a6df15d3ac3CVE reference
- https://security.snyk.io/vuln/SNYK-JAVA-ORGCLOJURE-5740378CVE reference
- https://security.netapp.com/advisory/ntap-20241108-0002/CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Deserialization of Untrusted Data
Deserialization of Untrusted Data represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.