PYSEC-2026-3873 Omnigent Guardrail policy bypass: shell-command parser fails open in policies/builtins/_shell.py

Reporter: Aaron / Aeon — autonomous security agent https://github.com/aaronjmars/aeon Project: omnigent-ai/omnigent v0.1.0 Databricks — meta-harness running Claude Code / Codex / Pi "in check with policies and sandboxing" Component: omnigent/policies/builtins/shell.py shared parser → consumed by...

PYSEC-2026-3874 Omnigent: Shared Agent Bundle Overwrite Leads to Authenticated Runner RCE

Summary An authenticated user with edit access to their own session can overwrite a shared/template agent by uploading a full agent bundle through PUT /sessions/sessionid/agent. Shared/template agents are shown as not MCP-editable, but this upload path still accepts a replacement bundle. By addin...

PYSEC-2026-3930 unstructured: Server-Side Request Forgery in the URL-based partitioning

Summary Server-Side Request Forgery in unstructured. The url= argument of partition, partitionhtml, and partitionmd is fetched via requests.get with no host validation. The response body is returned as Element text, so this is a full-read SSRF — attackers reach loopback admin APIs, internal HTTP...

Omnigent Guardrail policy bypass: shell-command parser fails open in policies/builtins/_shell.py

Reporter: Aaron / Aeon — autonomous security agent https://github.com/aaronjmars/aeonProject: omnigent-ai/omnigent v0.1.0 Databricks — meta-harness running Claude Code / Codex / Pi "in check with policies and sandboxing"Component: omnigent/policies/builtins/shell.py shared parser → consumed by...

PYSEC-2026-3875 Omnigent: Unvalidated os_env.cwd in agent bundle yields arbitrary host filesystem access on runners without OMNIGENT_RUNNER_WORKSPACE

Summary An authenticated, non-admin user can obtain arbitrary host-filesystem read/write and host environment-secret disclosure on an Omnigent runner by uploading an agent bundle whose osenv.cwd points outside any intended workspace e.g. / or /home/. The cwd field is taken verbatim from the bundl...

Omnigent: Uploaded Agent Bundle Allows Authenticated Runner RCE via Python Callable Tools

SummaryAn authenticated user can upload a crafted agent bundle that defines a server-side Python callable tool. The server validates the uploaded bundle, but it does not block dangerous callable: paths in untrusted user-provided agent configs.When the tool is invoked, the runner imports and...

RestrictedPython guard hooks can be shadowed via positional-only arguments

ImpactRestrictedPython rewrites sensitive operations to go through guard hooks. Attribute access becomes getattrobj, name, item access becomes getitemobj, key, writes go through write, and print goes through print. The embedding application supplies these hooks to enforce its policy.Argument-name...

PYSEC-2026-3917 RestrictedPython guard hooks can be shadowed via positional-only arguments

Impact RestrictedPython rewrites sensitive operations to go through guard hooks. Attribute access becomes getattrobj, name, item access becomes getitemobj, key, writes go through write, and print goes through print. The embedding application supplies these hooks to enforce its policy. Argument-na...

asyncssh has SCP Path Traversal to Arbitrary File Write

| | ||---|---|| Product | asyncssh all versions through 2.23.0 || Related | CVE-2019-6111 same class in OpenSSH || Fix | AsyncSSH 2.23.1 |A malicious SSH server can write arbitrary files on the asyncssh SCP client's filesystem by sending filenames containing ../ traversal sequences. The SCP recei...

aiosmtplib: STARTTLS response injection

ImpactWhen a connection is upgraded with STARTTLS, aiosmtplib reads the server's 220 go-ahead reply and immediately performs the TLS handshake without discarding any data still sitting in the receive buffer. Bytes the protocol read off the plaintext socket before the handshake survive across the...

WebOb: Open redirect in Location header normalization via leading C0 control / space characters

SummaryThis is a third follow-up to CVE-2024-42353 / GHSA-mg3v-6m49-jhp3and CVE-2026-44889 / GHSA-fh3h-vg37-cc95.WebOb makes the Location header absolute when it serves a redirect. To stop arelative or protocol-relative target from redirecting users off-host, it checksthe value for a URI scheme a...

Trestle has Server-Side Template Injection (SSTI) via Recursive Template Re-evaluation of Untrusted Data

ImpactA Server-Side Template Injection SSTI vulnerability exists in multiple locations of trestle's Jinja2 rendering pipeline due to a systemic pattern: untrusted data is re-parsed as Jinja2 template source code without sandboxing. This advisory tracks the root cause across all affected code...

PYSEC-2026-3805 aiosmtplib: STARTTLS response injection

Impact When a connection is upgraded with STARTTLS, aiosmtplib reads the server's 220 go-ahead reply and immediately performs the TLS handshake without discarding any data still sitting in the receive buffer. Bytes the protocol read off the plaintext socket before the handshake survive across the...

PYSEC-2026-3809 asyncssh has an incomplete fix for CVE-2026-45309 — AuthorizedKeysFile %u still escapes the intended directory via a leading ~ (and weakly via ${ENV}) username substitution

Incomplete fix for CVE-2026-45309 GHSA-g794-3fmp-753h. The 2.23.0 guard that sanitises the SSH username before %u substitution in AuthorizedKeysFile blocks /, \ and .., but does not block a leading or $ENV, both of which are re-introduced by later expansion and reach the file open — defeating the...

asyncssh has an incomplete fix for CVE-2026-45309 — AuthorizedKeysFile %u still escapes the intended directory via a leading ~ (and weakly via ${ENV}) username substitution

Incomplete fix for CVE-2026-45309 GHSA-g794-3fmp-753h. The 2.23.0 guard that sanitises the SSH username before %u substitution in AuthorizedKeysFile blocks /, \ and .., but does not block a leading or $ENV, both of which are re-introduced by later expansion and reach the file open — defeating the...

PYSEC-2026-3808 asyncssh has SCP Path Traversal to Arbitrary File Write

| | | |---|---| | Product | asyncssh all versions through 2.23.0 | | Related | CVE-2019-6111 same class in OpenSSH | | Fix | AsyncSSH 2.23.1 | A malicious SSH server can write arbitrary files on the asyncssh SCP client's filesystem by sending filenames containing ../ traversal sequences. The SCP...

PYSEC-2026-3943 WebOb: Open redirect in Location header normalization via leading C0 control / space characters

Summary This is a third follow-up to CVE-2024-42353 / GHSA-mg3v-6m49-jhp3 and CVE-2026-44889 / GHSA-fh3h-vg37-cc95. WebOb makes the Location header absolute when it serves a redirect. To stop a relative or protocol-relative target from redirecting users off-host, it checks the value for a URI...

PYSEC-2026-3817 Trestle has Server-Side Template Injection (SSTI) via Recursive Template Re-evaluation of Untrusted Data

Impact A Server-Side Template Injection SSTI vulnerability exists in multiple locations of trestle's Jinja2 rendering pipeline due to a systemic pattern: untrusted data is re-parsed as Jinja2 template source code without sandboxing. This advisory tracks the root cause across all affected code...

PYSEC-2026-3812 Chainlit has command injection via MCP stdio transport that allows unauthenticated remote code execution

Am I affected? Only if your deployment sets features.mcp.enabled = true in .chainlit/config.toml. MCP has been disabled by default since v2.7.0, so most Chainlit deployments are not affected. No authentication is required: /mcp is reachable by any client that can open a session. Summary When MCP ...

PYSEC-2026-3811 Chainlist has SSRF via MCP SSE and streamable-http transports that allows unauthenticated internal network access

Am I affected? Only if your deployment sets features.mcp.enabled = true in .chainlit/config.toml. MCP has been disabled by default since v2.7.0, so most Chainlit deployments are not affected. No authentication is required: /mcp is reachable by any client that can open a session. Summary When MCP ...