{"cve":{"cve_id":"CVE-2026-23950","is_kev":false,"kev_date_added":null,"kev_vendor_project":null,"kev_product":null,"kev_vulnerability_name":null,"kev_short_description":null,"kev_required_action":null,"kev_due_date":null,"kev_known_ransomware":null,"kev_notes":null,"kev_cwes":null,"epss_score":0.00153,"epss_percentile":0.04753,"epss_as_of":"2026-06-23","description":"node-tar,a Tar for Node.js, has a race condition vulnerability in versions up to and including 7.5.3. This is due to an incomplete handling of Unicode path collisions in the `path-reservations` system. On case-insensitive or normalization-insensitive filesystems (such as macOS APFS, In which it has been tested), the library fails to lock colliding paths (e.g., `ß` and `ss`), allowing them to be processed in parallel. This bypasses the library's internal concurrency safeguards and permits Symlink Poisoning attacks via race conditions. The library uses a `PathReservations` system to ensure that metadata checks and file operations for the same path are serialized. This prevents race conditions where one entry might clobber another concurrently. This is a Race Condition which enables Arbitrary File Overwrite. This vulnerability affects users and systems using node-tar on macOS (APFS/HFS+). Because of using `NFD` Unicode normalization (in which `ß` and `ss` are different), conflicting paths do not have their order properly preserved under filesystems that ignore Unicode normalization (e.g., APFS (in which `ß` causes an inode collision with `ss`)). This enables an attacker to circumvent internal parallelization locks (`PathReservations`) using conflicting filenames within a malicious tar archive. The patch in version 7.5.4 updates `path-reservations.js` to use a normalization form that matches the target filesystem's behavior (e.g., `NFKD`), followed by first `toLocaleLowerCase('en')` and then `toLocaleUpperCase('en')`. As a workaround, users who cannot upgrade promptly, and who are programmatically using `node-tar` to extract arbitrary tarball data should filter out all `SymbolicLink` entries (as npm does) to defend against arbitrary file writes via this file system entry name collision issue.","published_at":"2026-01-20T00:40:48.510000Z","last_modified_at":null,"cvss_v3_score":8.8,"cvss_v3_vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:H/A:L","cvss_v3_severity":"HIGH","cvss_v4_score":null,"cvss_v4_vector":null,"cvss_v4_severity":null,"ssvc_decision":null,"ssvc_exploitation":null,"ssvc_automatable":null,"ssvc_technical_impact":null,"cwes":["CWE-176","CWE-352","CWE-367"],"nvd_references":["https://github.com/isaacs/node-tar/security/advisories/GHSA-r6q2-hw4h-h46w","https://github.com/isaacs/node-tar/commit/3b1abfae650056edfabcbe0a0df5954d390521e6"],"vuln_status":null,"trending_score":null,"is_trending":false,"has_trended":false,"trended_number_one":false,"trending_peak_score":null,"trending_peak_rank":null,"started_trending_at":null,"trended_number_one_at":null,"summary_generated":null,"summary_generated_at":null,"summary_model":null,"created_at":"2026-06-24T00:09:39.878444Z","updated_at":"2026-06-28T23:29:18.510865Z"},"effective_severity":"HIGH","badges":[],"impact_analysis":[],"cvss_v3_decoded":{"version":"3.1","metrics":[{"metric":"AV","name":"Attack Vector","value":"N","value_label":"Network"},{"metric":"AC","name":"Attack Complexity","value":"L","value_label":"Low"},{"metric":"PR","name":"Privileges Required","value":"N","value_label":"None"},{"metric":"UI","name":"User Interaction","value":"R","value_label":"Required"},{"metric":"S","name":"Scope","value":"C","value_label":"Changed"},{"metric":"C","name":"Confidentiality","value":"L","value_label":"Low"},{"metric":"I","name":"Integrity","value":"H","value_label":"High"},{"metric":"A","name":"Availability","value":"L","value_label":"Low"}]},"cvss_v4_decoded":{"version":null,"metrics":[]},"affected":[{"vendor_slug":"isaacs","vendor_name":"isaacs","product_slug":"node-tar","product_name":"node-tar","version_start":"< 7.5.4","version_start_inclusive":true,"version_end":"< 7.5.4","version_end_inclusive":true,"cpe23_uri":"cve5:isaacs:node-tar:< 7.5.4:< 7.5.4"}],"exploit_refs":[],"news":[],"references":[{"url":"https://github.com/isaacs/node-tar/security/advisories/GHSA-r6q2-hw4h-h46w","source_type":"VENDOR_ADVISORY","tags":["advisory"]},{"url":"https://github.com/isaacs/node-tar/commit/3b1abfae650056edfabcbe0a0df5954d390521e6","source_type":"PATCH","tags":["patch"]}],"timeline":[{"type":"published","at":"2026-01-20T00:40:48.510000Z","label":"CVE published","source":null},{"type":"cvss_changed","at":"2026-06-28T17:51:54.153642Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:51:54.153642Z","label":"CVSS score revised","source":"cvelistv5"},{"type":"cvss_changed","at":"2026-06-28T17:51:54.153642Z","label":"CVSS score revised","source":"cvelistv5"}]}