Description
The insights-runtime-extractor runs as a privileged DaemonSet (`hostPID: true`)
that scans container processes for runtime fingerprinting. When scanning a
container, the coordinator:
1. **fork()s** a child process
2. **setns()** into the target container's PID and mount namespaces
3. **fchdir()** back to an orphaned FD pointing at the extractor's own root
filesystem (where `/crio.sock` is hostPath-mounted)
4. Calls **only `seteuid(target_uid)`** — changing the effective UID but leaving
the **real UID and saved-set-UID at 0** and **retaining the permitted
capability set**
5. The `check_no_privileged_perms()` guard inspects only the Effective capability
set (so it passes), and is **skipped entirely when the target runs as uid 0**
6. The `VersionExecutable` fingerprint invokes `fpr_kind_executable` with
`process.command_line[0]` — the target's argv[0], read from
`/proc/<pid>/cmdline` and **fully controlled by the workload**
7. `fpr_kind_executable` calls `exec.Command(executable, "--version").Output()`
— executing the **workload's own binary** inside the workload's mount
namespace while **ruid=0 in the host user namespace**
The executed process can call `setuid(0)` to restore full root with
`CAP_SYS_ADMIN`, and inherits the orphaned cwd which resolves into the extractor
container's filesystem containing the host CRI-O socket.
## Affected Code
### 1. Insufficient privilege drop (Rust — extractor coordinator)
**File:** `extractor/src/insights_runtime_extractor.rs`
```rust
// Lines 139-146 — seteuid-only drop, guard skipped for root containers
join_process_namespaces(process.pid)?;
change_dir(current_dir);
switch_user(*process.uid)?;
if *process.uid != 0 {
perms::check_no_privileged_perms()
.expect("Must not have privileged permissions to run fingerprints");
}
fingerprint::run_fingerprints(&config, out_dir, &process);
```
```rust
// Lines 182-185 — only effective UID changed; ruid/suid stay 0
fn switch_user(uid: u32) -> Result<(), ScannerError> {
debug!("... Becoming user: {uid}");
seteuid(uid.into()).map_err(|e| ScannerError::Errno(e))
}
```
### 2. Execution of untrusted binary (Go — fingerprint)
**File:** `fingerprints/pkg/utils/file.go`
```go
// Lines 75-80 — executes a path taken verbatim from workload's argv[0]
func GetExecutableVersionOutput(executable string) (string, error) {
out, err := exec.Command(executable, "--version").Output()
if err != nil {
return "", err
}
return string(out), nil
}
```
### 3. Workload-controlled path forwarded (Rust — version_executable)
**File:** `version_executable.rs`
```rust
// Lines 29-34 — workload-controlled command_line[0] forwarded to fingerprint
return Some(vec![
fpr_kind_executable,
out_dir.to_string(),
String::from(&process.command_line[0]),
String::from(&version_executable.runtime_kind_name),
]);
```
## Attack Pattern
**Attacker:** Any tenant able to schedule a pod (unprivileged, any namespace)
**Victim:** The node running the insights-runtime-extractor DaemonSet
**Trigger:** Automatic — the DaemonSet scans all container processes on the node
**Attack sequence:**
1. Attacker creates a pod whose process name matches a configured
versioned-executable pattern (`node`, `python`, `python3`, `MainThread`,
or contains `java`)
2. The pod's main binary (at the path matching argv[0]) is a malicious
executable that calls `setuid(0)` to restore root
3. When the insights operator triggers a scan, the DaemonSet forks, enters the
attacker's mount namespace, and executes the attacker's binary with ruid=0
4. The attacker's code regains full root with `CAP_SYS_ADMIN` in the host user
namespace
5. The inherited cwd contains the host CRI-O socket → full node compromise
that scans container processes for runtime fingerprinting. When scanning a
container, the coordinator:
1. **fork()s** a child process
2. **setns()** into the target container's PID and mount namespaces
3. **fchdir()** back to an orphaned FD pointing at the extractor's own root
filesystem (where `/crio.sock` is hostPath-mounted)
4. Calls **only `seteuid(target_uid)`** — changing the effective UID but leaving
the **real UID and saved-set-UID at 0** and **retaining the permitted
capability set**
5. The `check_no_privileged_perms()` guard inspects only the Effective capability
set (so it passes), and is **skipped entirely when the target runs as uid 0**
6. The `VersionExecutable` fingerprint invokes `fpr_kind_executable` with
`process.command_line[0]` — the target's argv[0], read from
`/proc/<pid>/cmdline` and **fully controlled by the workload**
7. `fpr_kind_executable` calls `exec.Command(executable, "--version").Output()`
— executing the **workload's own binary** inside the workload's mount
namespace while **ruid=0 in the host user namespace**
The executed process can call `setuid(0)` to restore full root with
`CAP_SYS_ADMIN`, and inherits the orphaned cwd which resolves into the extractor
container's filesystem containing the host CRI-O socket.
## Affected Code
### 1. Insufficient privilege drop (Rust — extractor coordinator)
**File:** `extractor/src/insights_runtime_extractor.rs`
```rust
// Lines 139-146 — seteuid-only drop, guard skipped for root containers
join_process_namespaces(process.pid)?;
change_dir(current_dir);
switch_user(*process.uid)?;
if *process.uid != 0 {
perms::check_no_privileged_perms()
.expect("Must not have privileged permissions to run fingerprints");
}
fingerprint::run_fingerprints(&config, out_dir, &process);
```
```rust
// Lines 182-185 — only effective UID changed; ruid/suid stay 0
fn switch_user(uid: u32) -> Result<(), ScannerError> {
debug!("... Becoming user: {uid}");
seteuid(uid.into()).map_err(|e| ScannerError::Errno(e))
}
```
### 2. Execution of untrusted binary (Go — fingerprint)
**File:** `fingerprints/pkg/utils/file.go`
```go
// Lines 75-80 — executes a path taken verbatim from workload's argv[0]
func GetExecutableVersionOutput(executable string) (string, error) {
out, err := exec.Command(executable, "--version").Output()
if err != nil {
return "", err
}
return string(out), nil
}
```
### 3. Workload-controlled path forwarded (Rust — version_executable)
**File:** `version_executable.rs`
```rust
// Lines 29-34 — workload-controlled command_line[0] forwarded to fingerprint
return Some(vec![
fpr_kind_executable,
out_dir.to_string(),
String::from(&process.command_line[0]),
String::from(&version_executable.runtime_kind_name),
]);
```
## Attack Pattern
**Attacker:** Any tenant able to schedule a pod (unprivileged, any namespace)
**Victim:** The node running the insights-runtime-extractor DaemonSet
**Trigger:** Automatic — the DaemonSet scans all container processes on the node
**Attack sequence:**
1. Attacker creates a pod whose process name matches a configured
versioned-executable pattern (`node`, `python`, `python3`, `MainThread`,
or contains `java`)
2. The pod's main binary (at the path matching argv[0]) is a malicious
executable that calls `setuid(0)` to restore root
3. When the insights operator triggers a scan, the DaemonSet forks, enters the
attacker's mount namespace, and executes the attacker's binary with ruid=0
4. The attacker's code regains full root with `CAP_SYS_ADMIN` in the host user
namespace
5. The inherited cwd contains the host CRI-O socket → full node compromise
Analysis
Analysis and contextual insights are available on OpenCVE Cloud.
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions |
|---|---|---|---|
| Red Hat | Red Hat OpenShift Container Platform 4 | affected | — |
No data.
No data.
No data available yet.
Remediation
Vendor Workaround
The vulnerability requires a code fix to implement a complete privilege drop (setting all three UID/GID fields, clearing all Linux capability sets, and setting `PR_SET_NO_NEW_PRIVS`) before executing any fingerprint binary.
Tracking
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Advisories
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References
History
Wed, 14 Oct 2026 11:00:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | The insights-runtime-extractor runs as a privileged DaemonSet (`hostPID: true`) that scans container processes for runtime fingerprinting. When scanning a container, the coordinator: 1. **fork()s** a child process 2. **setns()** into the target container's PID and mount namespaces 3. **fchdir()** back to an orphaned FD pointing at the extractor's own root filesystem (where `/crio.sock` is hostPath-mounted) 4. Calls **only `seteuid(target_uid)`** — changing the effective UID but leaving the **real UID and saved-set-UID at 0** and **retaining the permitted capability set** 5. The `check_no_privileged_perms()` guard inspects only the Effective capability set (so it passes), and is **skipped entirely when the target runs as uid 0** 6. The `VersionExecutable` fingerprint invokes `fpr_kind_executable` with `process.command_line[0]` — the target's argv[0], read from `/proc/<pid>/cmdline` and **fully controlled by the workload** 7. `fpr_kind_executable` calls `exec.Command(executable, "--version").Output()` — executing the **workload's own binary** inside the workload's mount namespace while **ruid=0 in the host user namespace** The executed process can call `setuid(0)` to restore full root with `CAP_SYS_ADMIN`, and inherits the orphaned cwd which resolves into the extractor container's filesystem containing the host CRI-O socket. ## Affected Code ### 1. Insufficient privilege drop (Rust — extractor coordinator) **File:** `extractor/src/insights_runtime_extractor.rs` ```rust // Lines 139-146 — seteuid-only drop, guard skipped for root containers join_process_namespaces(process.pid)?; change_dir(current_dir); switch_user(*process.uid)?; if *process.uid != 0 { perms::check_no_privileged_perms() .expect("Must not have privileged permissions to run fingerprints"); } fingerprint::run_fingerprints(&config, out_dir, &process); ``` ```rust // Lines 182-185 — only effective UID changed; ruid/suid stay 0 fn switch_user(uid: u32) -> Result<(), ScannerError> { debug!("... Becoming user: {uid}"); seteuid(uid.into()).map_err(|e| ScannerError::Errno(e)) } ``` ### 2. Execution of untrusted binary (Go — fingerprint) **File:** `fingerprints/pkg/utils/file.go` ```go // Lines 75-80 — executes a path taken verbatim from workload's argv[0] func GetExecutableVersionOutput(executable string) (string, error) { out, err := exec.Command(executable, "--version").Output() if err != nil { return "", err } return string(out), nil } ``` ### 3. Workload-controlled path forwarded (Rust — version_executable) **File:** `version_executable.rs` ```rust // Lines 29-34 — workload-controlled command_line[0] forwarded to fingerprint return Some(vec![ fpr_kind_executable, out_dir.to_string(), String::from(&process.command_line[0]), String::from(&version_executable.runtime_kind_name), ]); ``` ## Attack Pattern **Attacker:** Any tenant able to schedule a pod (unprivileged, any namespace) **Victim:** The node running the insights-runtime-extractor DaemonSet **Trigger:** Automatic — the DaemonSet scans all container processes on the node **Attack sequence:** 1. Attacker creates a pod whose process name matches a configured versioned-executable pattern (`node`, `python`, `python3`, `MainThread`, or contains `java`) 2. The pod's main binary (at the path matching argv[0]) is a malicious executable that calls `setuid(0)` to restore root 3. When the insights operator triggers a scan, the DaemonSet forks, enters the attacker's mount namespace, and executes the attacker's binary with ruid=0 4. The attacker's code regains full root with `CAP_SYS_ADMIN` in the host user namespace 5. The inherited cwd contains the host CRI-O socket → full node compromise | |
| Title | Insights-runtime-extractor: insights-runtime-extractor: container escape via privileged binary execution | |
| First Time appeared |
Redhat
Redhat openshift |
|
| Weaknesses | CWE-250 | |
| CPEs | cpe:/a:redhat:openshift:4 | |
| Vendors & Products |
Redhat
Redhat openshift |
|
| References |
| |
| Metrics |
cvssV3_1
|
MITRE
Status: PUBLISHED
Assigner: redhat
Published:
Updated: 2026-10-14T10:55:17.144Z
Reserved: 2026-10-02T13:07:13.820Z
Link: CVE-2026-104795
Vulnrichment
No data.
NVD
Status : Received
Published: 2026-10-14T11:16:59.937
Modified: 2026-10-14T11:16:59.937
Link: CVE-2026-104795
Redhat
No data.
OpenCVE Enrichment
No data.
Weaknesses