Vulnerability in proot-distro (CVE-2026-54574)
Summary
Vulnerability in proot-distro (CVE-2026-54574). Confidential information can be exposed externally. Exploitable via member.linkname. Mitigation: upgrade to 5.1.5 or later.
Original description
The description as published by the source.
Repository: termux/proot-distro
Component: proot_distro/commands/install.py → _extract_plain_tar(); also helpers/docker.py → _apply_layer()
Affected Versions
| Component | Version |
|---|---|
| proot-distro | 5.0.2 (confirmed vulnerable) |
| Termux app | 0.119.0-beta.3 |
| Device / ABI | Samsung Galaxy A23 / aarch64 |
| Python (host) | 3.13 |
Vulnerability Description
proot-distro install extracts a plain tarball rootfs by calling _extract_plain_tar() in
proot_distro/commands/install.py. This function correctly rejects tar member names
containing .. components, but applies no equivalent check on symlink targets
(member.linkname). A tar archive can therefore:
- Plant a symlink inside the rootfs whose target is an absolute host path
(e.g./data/data/com.termux/files/home). - Write a subsequent regular-file member whose path traverses through that symlink name.
Python's open() follows the symlink, writing the file on the host filesystem at the
privilege level of the Termux process — entirely during proot-distro install, before the
container is ever run.
The same _extract_plain_tar function is reachable via proot-distro reset, and the
equivalent _apply_layer in helpers/docker.py contains the same flaw.
Vulnerable Code
proot_distro/commands/install.py, `_extract_plain_t…
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-54574 has been found in proot-distro.
Attackers can target a specific entry point like member.linkname over the network to misuse the product.
Confidential information can be exposed externally. CVSS score: 8.2/10.
What to do: upgrade proot-distro to 5.1.5 or later.
If unsure, ask your IT team or search "proot-distro CVE-2026-54574" on the vendor's site.
CVE-2026-54574 (proot-distro) — CWE-61 / CVSS v3 8.2
Attack vector: local / unauthenticated
Attack surface: member.linkname / _extract_plain_tar / _apply_layer / rel_path
Patched: 5.1.5 — apply immediately
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-61) exists in proot-distro. Attackers reach the vulnerable code path via member.linkname without authentication.
Check the vendor advisory for the affected versions of proot-distro. Attack surface: member.linkname / _extract_plain_tar / _apply_layer / rel_path.
Severity: High (CVSS 8.2/10). Confidential information can be exposed externally.
Update to 5.1.5.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'proot-distro' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'proot-distro' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
proot-distroを grep し、稼働しているサービス・バージョンを把握する。 -
2Apply patch patch
Upgrade proot-distro to 5.1.5ステージング環境で 5.1.5 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
-
3Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。
Affected packages
References
- advisory github.com
- advisory nvd.nist.gov
- package github.com
- package pypi.org
- web github.com
- web github.com
- web github.com