# CVE-2026-73566: node-tar: Uncontrolled recursion in mapHas/filesFilter allows uncatchable stack-overflow DoS via crafted long-path tar with member selection

> Attackers can cause uncatchable stack overflow and application crash in Node.js applications using node-tar by providing crafted tar archives with long paths.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 13 Aug 2026
- **Updated:** 21 Aug 2026
- **Also known as:** CLEANSTART-2026-ED22669, CLEANSTART-2026-EG50639, CLEANSTART-2026-FT30855, CLSA-2026-1784856442, DEBIAN-CVE-2026-73566, ECHO-8eb3-d0ef-aa59, GHSA-r292-9mhp-454m, MINI-22xg-3g4q-3rpr, MINI-3fvc-xwg8-jj86, MINI-3g2x-8f6q-q6xq, MINI-3j45-q97q-3mmx, MINI-3r2g-wmph-pj9x, MINI-55m9-pjf8-pmj9, MINI-76pc-c5gc-hc6m, MINI-774r-qgg2-2r9q, MINI-7q2r-jvrm-7hpj, MINI-85c7-jqqg-f4m7, MINI-8jvw-wgv3-hp5j, MINI-8rp8-jxvw-wqxc, MINI-963r-3c73-9v6j, MINI-96mg-vg6r-rfr3, MINI-9h7r-572q-36hv, MINI-9w9j-j724-6ff6, MINI-c353-jv73-m2cf, MINI-cj7j-pccv-8hcq, MINI-cphh-j5hh-x73g, MINI-gj7v-cch8-hwqw, MINI-gp33-6h6f-mp6v, MINI-gwgq-v8mh-g5rp, MINI-h5xg-5mj2-67p3, MINI-h92c-mjhp-6h2p, MINI-hf2c-hhj8-5qpm, MINI-hm3c-7crw-5fj2, MINI-j99h-65wq-xh9p, MINI-pf96-24rf-95mh, MINI-q9g2-h5h5-928q, MINI-rq36-j77r-xxfx, MINI-v2qg-xwh5-c3jf, MINI-wpjv-rrgj-gm65, MINI-xchj-69c3-h6rm, ROOT-APP-NPM-CVE-2026-73566, ROOT-APP-NPM-GHSA-r292-9mhp-454m, UBUNTU-CVE-2026-73566

## What is CVE-2026-73566?

CVE-2026-73566 is a high-severity denial of service vulnerability in isaacs node-tar, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

node-tar is a tar archive manipulation library for Node.js. Prior to 7.5.21, node-tar's filesFilter in src/list.ts uses the recursive mapHas helper to walk an archive entry path upward with path.dirname() and no segment cap when tar.t(...) or tar.x(...) receives a non-empty member-selection list. A crafted GNU L or PAX x long-path header with thousands of slash-separated segments reaches this.filter(entry.path, entry) in Parser[CONSUMEHEADER] in src/parse.ts before Unpack[CHECKPATH] applies maxDepth, causing an uncatchable RangeError stack overflow that terminates asynchronous and streaming Node.js consumers. This issue is fixed in version 7.5.21.

Weakness: CWE-674 (Uncontrolled Recursion), CWE-400 (Uncontrolled Resource Consumption)

## Which versions are affected by CVE-2026-73566?

2 open source packages ship an affected version, including tar.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `tar` | npm | All versions | 7.5.21 |
| `tar` | npm | All versions | 7.5.21 |

## How do I fix CVE-2026-73566?

Upgrade tar to 7.5.21 or later.

## Is CVE-2026-73566 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73566 exists.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-73566 and fix it if it is affected.

What it is: CVE-2026-73566 is a high-severity denial of service vulnerability in isaacs node-tar, published on 13 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-73566 exists.

Affected packages and fixed versions:
- tar (npm): affected all versions; fixed in 7.5.21
- tar (npm): affected all versions; fixed in 7.5.21

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-73566/ (Markdown: https://insights.sbomify.com/CVE-2026-73566/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-73566
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-73566
- OSV: https://osv.dev/vulnerability/CVE-2026-73566

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-73566/
Summaries are generated and may contain mistakes; the official description above is the record.