Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:L) | Local access needed |
| Attack complexity (AC:L) | Low complexity |
| Privileges required (PR:N) | No privileges required |
| User interaction (UI:R) | A user must take an action |
| Scope (S:U) | Scope unchanged |
| Confidentiality (C:H) | High confidentiality impact |
| Integrity (I:H) | High integrity impact |
| Availability (A:N) | No availability impact |
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:N
About Isaacs Tar
CVE-2026-26960 affects Isaacs Tar, a product from Isaacs. Before acting, confirm where Isaacs Tar runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: node-tar is a full-featured Tar for Node.js. When using default options in versions 7.5.7 and below, an attacker-controlled archive can create a hardlink inside the extraction directory that points to a file outside the extraction root, enabling arbitrary file read and write as the extracting user. Severity is high because the primitive bypasses path protections and turns archive extraction into a direct filesystem access primitive. This issue has been fixed in version 7.5.8.
The weakness class is Path Traversal. An attacker can reach files outside the intended folder by tampering with a file path.
Based on its CVSS vector, the flaw needs local or adjacent access, needs no login, and relies on a user taking an action. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Isaacs Tar |
| Affected versions | Tar before 7.5.8 |
| Published | Feb 20, 2026 |
| Last modified | Jun 17, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | security-advisories@github.com |
How to detect it
- Inventory every instance of Isaacs Tar and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Isaacs Tar named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Isaacs Tar to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
- CWE-22: Path Traversal More CVEs with this weakness
Technical References
Frequently asked questions
Related CVEs
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