CVE Intelligence
Medium File handling exploit reference

CVE-2026-29786 — node-tar: Hardlink Path Traversal via Drive-Relative Linkpath

node-tar is a full-featured Tar for Node.js. Prior to version 7.5.10, tar can be tricked into creating a hardlink that points outside the extraction directory by using a drive-relative link target such as C:../target.txt, which enables file overwrite outside cwd during normal tar.x() extraction. This issue has been patched in version 7.5.10.

Published Mar 7, 2026 · Updated Oct 13, 2026 · Sources: NIST National Vulnerability Database, CVE Program (cve.org) e CISA ADP · CNA: GitHub_M

Who exploits it and how urgent it is

A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.

No exploitation signal in the sources consulted so far.
How the score was calculated
  • EPSS 0.4% (30-day exploitation probability)+5
  • Technical severity (medium)+3
  • CISA SSVC: exploitation "poc"+5

The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).

Triage

Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.

Exploitation
Not confirmed
Not in CISA KEV — an absence of record, not proof it is unexploited.
EPSS FIRST
0.4%
ahead of 33% of scored CVEs · Oct 14, 2026
Affects
Isaacs
Node-tar and 1 more
CVSS base
6.3
Medium · 4 source(s)
Prioritization reference: 8.6 provisional

CISA SSVC assessment CISA

Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.

Exploitation
Proof of concept
none · proof-of-concept · active
Automatable
No
can an attacker script the kill-chain steps
Technical impact
Partial
partial · total control of the vulnerable component

Remediation

Fixes and mitigations documented by the sources — linked to the original advisory.

  • Documented patch — github.com (NIST National Vulnerability Database)

First 24 hours

Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.

  1. Identify exposed assets running the affected vendor/product/version combinations (Isaacs Node-tar, Isaacs Tar).
  2. Apply the fixed version or the patch documented under Remediation.
  3. Exploitation requires user interaction: tighten email/web filtering and warn affected users.
  4. Search available logs for exploit probes matching the vulnerability class (file handling), errors and authentication anomalies.

Affected scope

Vendor, product and versions as the sources word them.

VendorProductVersionsStatusSource
Isaacs Node-tar version < 7.5.10 Vulnerable CVE Program (cve.org) e CISA ADP
Isaacs Tar < 7.5.10 Vulnerable NIST National Vulnerability Database

Attack characteristics

The CVSS vector, decoded. It describes the attack, not your exposure to it.

Attack vector
Local
Attack complexity
Low
Privileges required
None
User interaction
Required
Scope
Changed
Confidentiality
None
Integrity
High
Availability
None

Every base score collected

Sources score independently and may disagree; each row says who scored it and under which version.

ScoreVersionSeverityExpl.ImpactScored by
8.2 CVSS 4.0 High — — security-advisories@github.com via NIST National Vulnerability Database
8.2 CVSS 4.0 High — — GitHub_M via CVE Program (cve.org) e CISA ADP
8.6 CVSS 3.1 High 3.9 4.0 0b0ca135-0b70-47e7-9f44-1890c2a1c46c via NIST National Vulnerability Database
6.3 CVSS 3.1 Medium 1.8 4.0 nvd@nist.gov via NIST National Vulnerability Database
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:C/C:N/I:H/A:N (score shown at the top: nvd@nist.gov)
Scoring entities (NIST, CNA, ADP) score independently; each score is shown with its origin. For prioritization we use 8.6 (0b0ca135-0b70-47e7-9f44-1890c2a1c46c via NIST National Vulnerability Database) as a conservative provisional reference — not a definitive official score.

Weakness MITRE

Weakness class according to MITRE’s CWE catalog.

CWE-22 · Path Traversal

Other CVEs with this weakness →

EPSS over time FIRST

Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.40%

Detection

Read off the CVSS vector and the weakness class. Starting points, not tested rules.

  • Local/physical vector: focus on endpoint telemetry (EDR) from affected hosts.
  • Monitor file creation in web directories and paths with traversal sequences (../).
endpoint telemetry (EDR)file integrity (FIM)

Timeline

What happened to this CVE, newest first.

  • 2026
  • Affected products added · isaacs/node-tar
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • SSVC assessment updated
    Oct 13, 2026 · CVE Program (cve.org) e CISA ADP
  • Record published
    Oct 13, 2026
  • Fix documented
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVSS changed · 6.3
    Oct 13, 2026 · NIST National Vulnerability Database
  • Source status changed · → Modified
    Oct 13, 2026 · NIST National Vulnerability Database
  • Record created in this database
    Oct 13, 2026 · NIST National Vulnerability Database
  • CVE published
    Mar 7, 2026 · GitHub_M

Source activity

Repeated readings are counted rather than listed.

  • 1× Official description updated · Oct 13, 2026 – Oct 13, 2026

References

5 on the record

Elsewhere on this site

Isaacs
every CVE for this vendor
File handling
same class
CWE-22
other pages naming this weakness

Related CVEs (same products)

  • CVE-2026-59875 node-tar: Uncaught Exception DoS via NUL byte in PAX path/linkpath records Jul 8, 2026
  • CVE-2026-59871 node-tar: Process crash via PAX numeric path type confusion Jul 8, 2026
  • CVE-2026-59873 node-tar: Decompression/parse DoS via unlimited input Jul 8, 2026
  • CVE-2026-59874 node-tar: Negative tar entry size causes infinite loop in archive replace Jul 8, 2026
  • CVE-2026-53655 node-tar applies PAX size override to intermediary GNU long-name/long-link headers, causing tar parser interpretation differential (file smuggling) Jun 22, 2026
  • CVE-2026-31802 node-tar Symlink Path Traversal via Drive-Relative Linkpath Mar 10, 2026

Not in any source we poll

Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.

  • No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
  • No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
  • No exploit packet captures, log samples, or incident case IDs supplied.

Answered from this record

Text assembled only from the fields above — no additional claims.

What should defenders know first?

CVE-2026-29786 is "node-tar: Hardlink Path Traversal via Drive-Relative Linkpath", rated Medium. It affects Node-tar (Isaacs); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 6.3 describes technical severity. EPSS 0.40% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.

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