Tools: CVE-2026-24686: TUF Luck: Escaping the Sandbox in go-tuf via TAP 4 Map Files

TUF Luck: Escaping the Sandbox in go-tuf via TAP 4 Map Files ## ⚠️ Exploit Status: POC ## Technical Details ## Affected Systems ## Code Analysis ## Commit: d361e2e ## Commit: bde5f18 ## Exploit Details ## Mitigation Strategies ## References Vulnerability ID: CVE-2026-24686 CVSS Score: 9.8 Published: 2026-01-26 A critical Path Traversal vulnerability in the go-tuf TAP 4 Multirepo client allows attackers to overwrite arbitrary files via malicious repository names in the map file. The go-tuf library, widely used for secure software updates, contained a path traversal flaw in its TAP 4 support. By crafting a malicious map file with traversal sequences in repository names (e.g., "../../etc/cron.d"), an attacker can force the client to write metadata files to arbitrary locations on the host system. This turns a routine update check into an Arbitrary File Write primitive, potentially leading to RCE. Fix path traversal in TAP 4 repo names via regex validation Refactor Key.ID() to prevent panics (Pre-cursor work) Read the full report for CVE-2026-24686 on our website for more details including interactive diagrams and full exploit analysis. Templates let you quickly answer FAQs or store snippets for re-use. Are you sure you want to hide this comment? It will become hidden in your post, but will still be visible via the comment's permalink. Hide child comments as well For further actions, you may consider blocking this person and/or reporting abuse CODE_BLOCK: + if !validRepoNamePattern.MatchString(name) { + return fmt.Errorf("%w: %q must start with alphanumeric...", ErrInvalidRepoName, name) + } Enter fullscreen mode Exit fullscreen mode CODE_BLOCK: + if !validRepoNamePattern.MatchString(name) { + return fmt.Errorf("%w: %q must start with alphanumeric...", ErrInvalidRepoName, name) + } CODE_BLOCK: + if !validRepoNamePattern.MatchString(name) { + return fmt.Errorf("%w: %q must start with alphanumeric...", ErrInvalidRepoName, name) + } - CWE ID: CWE-22 (Path Traversal) - Attack Vector: Network / Local (Configuration) - CVSS v3.1 (Est): 9.8 (Critical) - Impact: Arbitrary File Write / RCE - Affected Component: metadata/multirepo/multirepo.go - Status: Patched - Go applications using the-update-framework/go-tuf - Systems utilizing TAP 4 Multirepo configurations - Supply chain security tools built on go-tuf - theupdateframework/go-tuf: < Commit d361e2ea (Fixed in: Commit d361e2ea) - Internal Research: The fix commit implicitly demonstrates the exploit vector via the added test cases and validation logic. - Input Validation: Enforce strict alphanumeric naming conventions for repositories. - Principle of Least Privilege: Run update clients with minimal filesystem permissions. - Sandboxing: Use filesystem namespaces or containers to limit write access. - Update go-tuf to the latest version containing commit d361e2ea24e427581343dee5c7a32b485d79fcc0. - Audit existing TAP 4 map files for traversal sequences. - Rebuild any applications dependent on the vulnerable library. - go-tuf GitHub Repository - The Update Framework (TUF) Homepage