# CVE-2026-62947: OpenWrt: ACL bypass and arbitrary root file read via cgi-io cgi-download

> Attackers can bypass ACLs and read sensitive root files like /etc/shadow via path traversal in the cgi-io handler.

- **Severity:** Medium 4.9 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:N/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 15 Jul 2026
- **Updated:** 15 Jul 2026
- **Also known as:** GHSA-jw5r-xhf5-2xcq

## What is CVE-2026-62947?

CVE-2026-62947 is a medium-severity path traversal vulnerability in Openwrt Openwrt, published on 15 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

OpenWrt is a Linux operating system targeting embedded devices. Prior to 25.12.5, the cgi-download handler in cgi-io authorizes the requested path against the caller's ubus session file ACL before canonicalization, and rpcd session.c uses fnmatch() without FNM_PATHNAME, allowing traversal such as an allowed wildcard prefix followed by ../ to read root-readable files including /etc/shadow. This vulnerability is fixed in 25.12.5.

Weakness: CWE-22 (Improper Limitation of a Pathname to a Restricted Directory)

## Which versions are affected by CVE-2026-62947?

It affects 1 product.


Products: Openwrt Openwrt.

## How do I fix CVE-2026-62947?

No fix has been published for CVE-2026-62947 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-62947 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-62947 exists.

## Other vulnerabilities in Openwrt Openwrt

- [CVE-2020-28951](https://insights.sbomify.com/CVE-2020-28951/): Use after free in n/a (critical 9.8)
- [CVE-2026-62948](https://insights.sbomify.com/CVE-2026-62948/): Cross-site scripting in openwrt (critical 9.6)
- [CVE-2026-30871](https://insights.sbomify.com/CVE-2026-30871/): OpenWrt Project has Stack-based Buffer Overflow in DNS PTR Query (critical 9.5)
- [CVE-2026-30872](https://insights.sbomify.com/CVE-2026-30872/): OpenWrt Project has a Stack-based Buffer Overflow vulnerability via IPv6 reverse DNS lookup (critical 9.5)
- [CVE-2021-28961](https://insights.sbomify.com/CVE-2021-28961/): Command injection in n/a (high 8.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-62947 and fix it if it is affected.

What it is: CVE-2026-62947 is a medium-severity path traversal vulnerability in Openwrt Openwrt, published on 15 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-62947 exists.

Affected product: Openwrt Openwrt. No package-level version data is available, so check the vendor advisory linked from the reference page.

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-2026-62947/ (Markdown: https://insights.sbomify.com/CVE-2026-62947/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-62947
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-62947
- OSV: https://osv.dev/vulnerability/CVE-2026-62947

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-62947/
Summaries are generated and may contain mistakes; the official description above is the record.