Anthropics vulnerabilities, page 2

38 vulnerabilities

Known vulnerabilities in Anthropics products, newest first, with CVSS severity, EPSS, KEV listings and ransomware use, across 6 products.

6.3MediumCVE-2026-55407anthropics · buffa +1 moreBuffa: Memory Exhaustion Denial of Service in decode_unknown_field via Unbounded AllocationBuffa is a pure-Rust Protocol Buffers implementation with first-class protobuf editions support. Prior to 0.8.0, the decode_unknown_field function in buffa's protobuf decoder allocated heap memory in proportion to untrusted input (unknown fields in the serialized protobuf) without enforcing an allocation budget, affecting any message decoded from untrusted input using code generated with preserve_unknown_fields=true (the default); a small, well-formed payload of nested unknown fields inside a StartGroup could trigger roughly 22x memory amplification (for example a 64 MiB input forcing about 1.4 GB of heap allocation), and length-delimited unknown fields could be sized arbitrarily, so an unauthenticated attacker could crash a process through memory exhaustion because the top-level message size cap did not account for in-decode amplification. This issue is fixed in version 0.8.0.EPSS0.76%5.3MediumCVE-2026-47751anthropics · claude-code-actionClaude Code Action: Malicious MCP Server Configuration in PRs Enables Remote Code Execution and Secret ExfiltrationClaude Code Action is a general-purpose GitHub action that runs Claude Code on GitHub pull requests and issues. Prior to 1.0.74, because the action checked out attacker-controlled pull request head branches, read .mcp.json from the working directory via default setting sources, and unconditionally enabled all project MCP servers via enableAllProjectMcpServers, an attacker who opened a pull request containing a malicious .mcp.json file could achieve arbitrary code execution on the GitHub Actions runner and exfiltrate secrets available to the workflow (such as API keys and tokens) when a privileged user or an automatic trigger invoked the Claude action on the pull request. This issue is fixed in version 1.0.74, which restores .claude/ and .mcp.json from the pull request base branch before the CLI runs.EPSS0.77%10CriticalCVE-2026-39861anthropic · claude_code +2 moreClaude Code: Sandbox Escape via Symlink Following Allows Arbitrary File Write Outside WorkspaceClaude Code is an agentic coding tool. Prior to version 2.1.64, Claude Code's sandbox did not prevent sandboxed processes from creating symlinks pointing to locations outside the workspace. When Claude Code subsequently wrote to a path within such a symlink, its unsandboxed process followed the symlink and wrote to the target location outside the workspace without prompting the user for confirmation. This allowed a sandbox escape where neither the sandboxed command nor the unsandboxed app could independently write outside the workspace, but their combination could write to arbitrary locations, potentially leading to code execution outside the sandbox. Reliably exploiting this required the ability to add untrusted content into a Claude Code context window to trigger sandboxed code execution via prompt injection. Users on standard Claude Code auto-update have received this fix automatically. Users performing manual updates are advised to update to version 2.1.64 or later.EPSS0.80%9.1CriticalCVE-2026-25722anthropic · claude_code +2 moreClaude Code Vulnerable to Command Injection via Directory Change Bypasses Write ProtectionClaude Code is an agentic coding tool. Prior to version 2.0.57, Claude Code failed to properly validate directory changes when combined with write operations to protected folders. By using the cd command to navigate into sensitive directories like .claude, it was possible to bypass write protection and create or modify files without user confirmation. Reliably exploiting this required the ability to add untrusted content into a Claude Code context window. This issue has been patched in version 2.0.57.EPSS0.70%7.5HighCVE-2026-25724anthropic · claude_code +2 moreClaude Code Has Permission Deny Bypass Through Symbolic LinksClaude Code is an agentic coding tool. Prior to version 2.1.7, Claude Code failed to strictly enforce deny rules configured in settings.json when accessing files through symbolic links. If a user explicitly denied Claude Code access to a file (such as /etc/passwd) and Claude Code had access to a symbolic link pointing to that file, it was possible for Claude Code to read the restricted file through the symlink without triggering deny rule enforcement. This issue has been patched in version 2.1.7.EPSS0.67%10CriticalCVE-2026-25725anthropic · claude_code +2 moreClaude Code Has Sandbox Escape via Persistent Configuration Injection in settings.jsonClaude Code is an agentic coding tool. Prior to version 2.1.2, Claude Code's bubblewrap sandboxing mechanism failed to properly protect the .claude/settings.json configuration file when it did not exist at startup. While the parent directory was mounted as writable and .claude/settings.local.json was explicitly protected with read-only constraints, settings.json was not protected if it was missing. This allowed malicious code running inside the sandbox to create this file and inject persistent hooks (such as SessionStart commands) that would execute with host privileges when Claude Code was restarted. This issue has been patched in version 2.1.2.EPSS0.70%7.7HighCVE-2026-25723anthropic · claude_code +2 moreClaude Code Vulnerable to Command Injection via Piped sed Command Bypasses File Write RestrictionsClaude Code is an agentic coding tool. Prior to version 2.0.55, Claude Code failed to properly validate commands using piped sed operations with the echo command, allowing attackers to bypass file write restrictions. This vulnerability enabled writing to sensitive directories like the .claude folder and paths outside the project scope. Exploiting this required the ability to execute commands through Claude Code with the "accept edits" feature enabled. This issue has been patched in version 2.0.55.EPSS0.53%6.1MediumCVE-2026-46406anthropic · claude_code +2 moreClaude Code: Insecure Temporary File in /copy Command Enables Response Disclosure and Symlink-Based File WriteClaude Code is an agentic coding tool. From 2.1.59 until 2.1.128, the Claude Code /copy command wrote responses to a hardcoded, predictable path (/tmp/claude/response.md) without UID isolation, randomness, or symlink protection. The file was created world-readable (0644) in a world-traversable directory (0755), allowing any local user to read a privileged user's Claude response, which could contain secrets or credentials. Additionally, because the path was static and predictable, a local attacker could pre-create the directory and plant a symlink at the expected file path, causing the privileged process to follow the symlink and overwrite an attacker-chosen file with the response text. Exploiting this required a local unprivileged user on the same system and a privileged user to run the /copy command. This vulnerability is fixed in 2.1.128.EPSS0.15%8.5HighCVE-2026-44470anthropic · claude_desktop +1 moreClaude Desktop: Local Privilege Escalation via Directory Junction in CoworkVMServiceThe Claude Desktop app gives you Claude Code with a graphical interface built for running multiple sessions side by side. Prior to 1.3834.0, the CoworkVMService component in Claude Desktop for Windows ran as SYSTEM and did not validate whether the VM bundle directory was a real directory or an NTFS directory junction before creating files within it. A local non-elevated user could replace the user-writable VM bundle directory with a directory junction pointing to an attacker-chosen location, causing the service to create a SYSTEM-owned file in an arbitrary directory. This could be leveraged for local privilege escalation. This vulnerability is fixed in 1.3834.0.EPSS0.16%7.4HighCVE-2026-44467anthropic · claude_desktop +1 moreClaude Desktop: SSH Host Key Verification Bypass Allows Man-in-the-Middle Attack on Remote SessionsThe Claude Desktop app gives you Claude Code with a graphical interface built for running multiple sessions side by side. From 1.2581.0 to before 1.4304.0, Claude Desktop's SSH remote development feature verified only whether a hostname existed in ~/.ssh/known_hosts without comparing the server's presented host key against the stored key. This allowed a network-positioned attacker to present an arbitrary SSH host key and have the connection silently accepted, enabling a man-in-the-middle attack on remote development sessions. Successful exploitation required the attacker to be in a network position to intercept SSH traffic (e.g., via ARP spoofing, rogue Wi-Fi, or DNS poisoning) and the target hostname to already have an entry in the victim's known_hosts file. This vulnerability is fixed in 1.4304.0.EPSS0.22%7.7HighCVE-2026-24053anthropic · claude_code +2 moreCluade Code has a Path Restriction Bypass via ZSH Clobber which Allows Arbitrary File WritesClaude Code is an agentic coding tool. Prior to version 2.0.74, due to a Bash command validation flaw in parsing ZSH clobber syntax, it was possible to bypass directory restrictions and write files outside the current working directory without user permission prompts. Exploiting this required the user to use ZSH and the ability to add untrusted content into a Claude Code context window. This issue has been patched in version 2.0.74.EPSS0.52%7.4HighCVE-2026-24052anthropic · claude_code +2 moreClaude Code has a Domain Validation Bypass which Allows Automatic Requests to Attacker-Controlled DomainsClaude Code is an agentic coding tool. Prior to version 1.0.111, Claude Code contained insufficient URL validation in its trusted domain verification mechanism for WebFetch requests. The application used a startsWith() function to validate trusted domains (e.g., docs.python.org, modelcontextprotocol.io), this could have enabled attackers to register domains like modelcontextprotocol.io.example.com that would pass validation. This could enable automatic requests to attacker-controlled domains without user consent, potentially leading to data exfiltration. This issue has been patched in version 1.0.111.EPSS0.44%8.8HighCVE-2026-24887anthropic · claude_code +2 moreClaude Code has a Command Injection in find Command Bypasses User Approval PromptClaude Code is an agentic coding tool. Prior to version 2.0.72, due to an error in command parsing, it was possible to bypass the Claude Code confirmation prompt to trigger execution of untrusted commands through the find command. Reliably exploiting this required the ability to add untrusted content into a Claude Code context window. This issue has been patched in version 2.0.72.EPSS0.65%5.8MediumCVE-2026-34452anthropic · claude_sdk_for_python +6 moreClaude SDK for Python: Memory Tool Path Validation Race Condition Allows Sandbox EscapeThe Claude SDK for Python provides access to the Claude API from Python applications. From version 0.86.0 to before version 0.87.0, the async local filesystem memory tool in the Anthropic Python SDK validated that model-supplied paths resolved inside the sandboxed memory directory, but then returned the unresolved path for subsequent file operations. A local attacker able to write to the memory directory could retarget a symlink between validation and use, causing reads or writes to escape the sandbox. The synchronous memory tool implementation was not affected. This issue has been patched in version 0.87.0.EPSS0.14%6.3MediumCVE-2026-34451anthropic · claude_sdk_for_typescript +2 moreClaude SDK for TypeScript: Memory Tool Path Validation Allows Sandbox Escape to Sibling DirectoriesClaude SDK for TypeScript provides access to the Claude API from server-side TypeScript or JavaScript applications. From version 0.79.0 to before version 0.81.0, the local filesystem memory tool in the Anthropic TypeScript SDK validated model-supplied paths using a string prefix check that did not append a trailing path separator. A model steered by prompt injection could supply a crafted path that resolved to a sibling directory sharing the memory root's name as a prefix, allowing reads and writes outside the sandboxed memory directory. This issue has been patched in version 0.81.0.EPSS0.39%4.8MediumCVE-2026-34450anthropic · claude_sdk_for_python +6 moreClaude SDK for Python: Insecure Default File Permissions in Local Filesystem Memory ToolThe Claude SDK for Python provides access to the Claude API from Python applications. From version 0.86.0 to before version 0.87.0, the local filesystem memory tool in the Anthropic Python SDK created memory files with mode 0o666, leaving them world-readable on systems with a standard umask and world-writable in environments with a permissive umask such as many Docker base images. A local attacker on a shared host could read persisted agent state, and in containerized deployments could modify memory files to influence subsequent model behavior. Both the synchronous and asynchronous memory tool implementations were affected. This issue has been patched in version 0.87.0.EPSS0.17%7.3HighCVE-2026-35603anthropic · claude_code +2 moreClaude Code: Insecure System-Wide Configuration Loading Enables Local Privilege Escalation on WindowsClaude Code is an agentic coding tool. In versions prior to 2.1.75 on Windows, Claude Code loaded the system-wide default configuration from C:\ProgramData\ClaudeCode\managed-settings.json without validating directory ownership or access permissions. Because the ProgramData directory is writable by non-administrative users by default and the ClaudeCode subdirectory was not pre-created or access-restricted, a low-privileged local user could create this directory and place a malicious configuration file that would be automatically loaded for any user launching Claude Code on the same machine. Exploiting this would have required a shared multi-user Windows system and a victim user to launch Claude Code after the malicious configuration was placed. This issue has been fixed on version 2.1.75.EPSS0.15%8.8HighCVE-2026-33068anthropic · claude_code +2 moreClaude Code has a Workspace Trust Dialog Bypass via Repo-Controlled Settings FileClaude Code is an agentic coding tool. Versions prior to 2.1.53 resolved the permission mode from settings files, including the repo-controlled .claude/settings.json, before determining whether to display the workspace trust confirmation dialog. A malicious repository could set permissions.defaultMode to bypassPermissions in its committed .claude/settings.json, causing the trust dialog to be silently skipped on first open. This allowed a user to be placed into a permissive mode without seeing the trust confirmation prompt, making it easier for an attacker-controlled repository to gain tool execution without explicit user consent. This issue has been patched in version 2.1.53.EPSS0.59%