Security readout for executives and security teams
Plain-English summary
CVE-2020-7707 affects the property-expr package before 2.0.3. A vulnerable setter can allow prototype pollution, where attacker-controlled data changes shared JavaScript object behavior. In affected applications, that can undermine data integrity and may contribute to broader compromise depending on how the package is used.
Executive priority
Treat as high-priority dependency remediation for exposed applications, especially where untrusted user input is processed. There is no provided evidence of active exploitation, but the critical CVSS score and no-auth attack characteristics justify prompt inventory and upgrade work.
Technical view
The CVE describes prototype pollution in property-expr via its setter function. The listed affected product is property-expr, with versions before 2.0.3 identified as vulnerable. CVSS 3.1 is 9.8 critical, network exploitable, low complexity, no privileges, no user interaction, with high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is most likely in JavaScript applications or builds that include property-expr directly or transitively. The source bundle also references an org.webjars.npm package advisory, so Java applications consuming npm WebJars packaging may need dependency review too.
Exploitation context
The source bundle does not show CISA KEV listing or cited evidence of active exploitation. The CVSS vector indicates the flaw can be remotely reachable in vulnerable usage patterns, but real-world exploitability depends on whether attacker-controlled paths or values reach the setter.
Researcher notes
Do not assume every application using property-expr is directly exploitable. Validate whether attacker-controlled object paths or values can reach the affected setter. The bundle lacks CWE mapping and detailed exploit telemetry, so exposure assessment should combine dependency presence with reachable code review.
Mitigation direction
- Upgrade property-expr to version 2.0.3 or later where applicable.
- Review npm and WebJars dependency trees for transitive property-expr usage.
- Regenerate lockfiles after dependency updates and verify the resolved version.
- Check vendor advisories for framework-specific remediation guidance.
- Prioritize internet-facing services that process untrusted structured input.
Validation and detection
- Search SBOMs, lockfiles, and package manifests for property-expr versions before 2.0.3.
- Check Java dependency inventories for org.webjars.npm packaging references.
- Confirm production artifacts resolve to the remediated dependency version.
- Review code paths where untrusted input can influence property setters.
- Run existing dependency scanning after remediation to confirm closure.
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.
CVE-2020-7707 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/E:P/RL:U/RC:C
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:H/E:P/RL:U/RC:C3.95.9Primary 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/E:P/RL:U/RC:C
Source materials
- CVE List V5 sourceCVE List V5
- https://snyk.io/vuln/SNYK-JS-PROPERTYEXPR-598800CVE reference · x_refsource_MISC
- https://snyk.io/vuln/SNYK-JAVA-ORGWEBJARSNPM-598857CVE reference · x_refsource_MISC
- https://github.com/jquense/expr/commit/df846910915d59f711ce63c1f817815bceab5ff7CVE reference · x_refsource_MISC
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.