Security readout for executives and security teams
Plain-English summary
CVE-2021-4260 is an open redirect issue in oils-js, reportedly in core/Web.js. It could let a remote attacker abuse application redirects to send users or workflows to unintended locations. The source bundle identifies a patch commit, but affected versions are not specified.
Executive priority
Treat this as a moderate remediation item unless oils-js is used in externally reachable business workflows. Prioritize confirmation of exposure first because the source bundle does not name affected versions or active exploitation.
Technical view
The CVE maps to CWE-601 and has CVSS 3.1 score 6.3: AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L. The vulnerable component is oils-js core/Web.js, with affected versions listed only as n/a. The named fix is GitHub commit fad8fbae824a7d367dacb90d56cb02c5cb999d42.
Likely exposure
Exposure is likely limited to applications that directly use oils-js and exercise its Web.js redirect behavior. Version-level exposure cannot be determined from the provided sources because affected versions are not identified.
Exploitation context
The source says the attack can be initiated remotely and requires low complexity with low privileges. The CVE is not listed as CISA KEV in the bundle, and the provided sources do not establish active exploitation.
Researcher notes
Evidence is thin but sufficient to identify the class, component, and patch reference. Do not assume all oils-js versions are affected. Validate against the specific deployed source or package version and compare redirect handling to the patched commit.
Mitigation direction
- Apply the upstream patch commit fad8fbae824a7d367dacb90d56cb02c5cb999d42 where applicable.
- Check upstream oils-js guidance for a fixed release or supported upgrade path.
- Inventory applications and services that include oils-js.
- Review redirect destinations for allowlist-based controls where oils-js is used.
Validation and detection
- Confirm whether oils-js appears in application dependency manifests or vendored source.
- Verify deployed code includes the referenced patch or an upstream fixed release.
- Review reachable application paths that invoke core/Web.js redirect behavior.
- Check security scanners for CVE-2021-4260 coverage and validate findings manually.
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-601: User-session and phishing behavior lookup
Client-side and session-facing weaknesses should be reviewed alongside initial-access and user-execution behaviors. 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 lookupCVE-2021-4260 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
- Medium
- CVSS
- 6.3 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
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:L/UI:N/S:U/C:L/I:L/A:L2.83.4Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
6.3MediumVector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/mannyvergel/oils-js/commit/fad8fbae824a7d367dacb90d56cb02c5cb999d42CVE reference
- https://vuldb.com/?id.216268CVE 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.
URL Redirection to Untrusted Site ('Open Redirect')
URL Redirection to Untrusted Site ('Open Redirect') represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.