GHSA-8gmg-3w2q-65f4
### Summary A flaw in the Java agent injection path allows a local attacker controlling a Java workload to overwrite arbitrary host files when Java injection is enabled and OBI is running with elevated privileges. The injector trusted `TMPDIR` from the target process and used unsafe file creation semantics, enabling both filesystem boundary escape and symlink-based file clobbering. ### Remediation Upgrade to https://github.com/open-telemetry/opentelemetry-ebpf-instrumentation/releases/tag/v0.8.0. ### Details The issue is in the Java agent staging logic in `pkg/internal/java/java_inject.go`. The injector reads `TMPDIR` from the target process environment in `findTempDir(...)` and validates it with `dirOK(...)`. In the vulnerable implementation, `dirOK(...)` used `filepath.Join(root, dir)`, where `root` is `/proc/<pid>/root`. If `dir` is an absolute path, `filepath.Join` discards `root`, so values such as `/etc` or `/proc/1/root/etc` are resolved on the host instead of within the target process root. That validated value is later reused in `copyAgent(...)` to build the destination path for the Java agent JAR. As a result, a malicious process can influence the privileged injector to write outside the intended `/proc/<pid>/root` boundary. The file creation step further increases impact. The vulnerable code created the destination with `os.OpenFile(..., os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0o644)`. Because this does not use exclusive creation or symlink protections, an attacker can pre-create a symlink at the chosen destination, for example in a writable temp directory, and cause the injector to truncate or overwrite another file writable by the privileged OBI process. Relevant code paths: - `pkg/internal/java/java_inject.go`: `findTempDir(...)` - `pkg/internal/java/java_inject.go`: `dirOK(...)` - `pkg/internal/java/java_inject.go`: `copyAgent(...)` In short, the vulnerability is caused by two issues acting together: 1. Untrusted `TMPDIR` from the target proce
Properties
- ghsa_id
- GHSA-8gmg-3w2q-65f4
- summary
- OpenTelemetry eBPF Instrumentation: Privileged Java agent injection allows arbitrary host file overwrite via untrusted TMPDIR
- severity
- high
- cvss_score
- 8.4
- cve_id
- GHSA-8gmg-3w2q-65f4
- cvss_vector
- CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:H
- is_ghsa_only
- true
- ghsa_published
- 2026-04-17T22:21:41Z
- source_url
- https://github.com/advisories/GHSA-8gmg-3w2q-65f4
- ghsa_updated
- 2026-04-17T22:21:43Z
Related Entities (5)
REPORTED_BY (1)
VULNERABLE_TO (1)
AFFECTS (1)
HAS_WEAKNESS (2)
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