CVE-2026-88808
A vulnerability has been identified within Rancher Manager where the Fleet agent wrote resources to downstream clusters using its own cluste
CVSS
8.8
High
EPSS
0.3%
p20
KEV
—
Exploit Today
6
0-100
Published: Sep 28, 2026 · Last modified: Oct 7, 2026 · CWE-250
0.3%EPSS · 30 days0.3%
2026-09-292026-10-25
A vulnerability has been identified within Rancher Manager where the Fleet agent wrote resources to downstream clusters using its own cluster-admin credentials instead of the ServiceAccount pinned to the deployment. It affects multi-tenancy environments where different tenants share the same downstream clusters, for example different privileged or untrusted teams inside the same organization. This could lead to overwritten configuration files. This issue affected SUSE Rancher Fleet 0.16 before 0.16.2, 0.15 before 0.15.7, and 0.14 before 0.14.11.
CVECVSSEPSSKEVRExploitTitleMod.
CVE-2025-30046—18.0%
——5In the CGM CLININET application server, multiple processes responsible for HL7 communication with external systems run with root privileges while processing untrusted data received from those external systems. An attacker in adjacent network able to send data to these HL7 communication processes can achieve remote code execution with root privileges.
The vulnerability was confirmed to affect versions up to 2026.MS3 but later versions may also be vulnerable.3dCVE-2026-1047958.8 HIG5.0%
——2The 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 compromise6dCVE-2026-1101505.5 MED0.5%
——0Privilege elevation in Installer in Google Chrome on on Windows prior to 155.0.8059.79 allowed a local attacker to obtain sensitive information via a local program. (Chromium security severity: High)11dCVE-2026-877095.5 MED24.1%
——7Improper access control in Windows Host Guardian Service allows an authorized attacker to perform tampering locally.10dCVE-2026-6516210.0 CRI51.3%
——15NVIDIA AIStore for Linux contains a vulnerability in the legacy ETL Kubernetes PodSpec initialization API where a remote attacker may supply Kubernetes host-namespace and container-security settings. A successful exploit may lead to code execution, privilege escalation, information disclosure, data tampering, and denial of service.13dCVE-2026-756216.2 MED1.6%
——0IBM Aspera Enterprise WebApps 1.0.0 through 1.0.6 could allow a local attacker to obtain sensitive information due to excessive permissions assigned to a service account.13d