CVE-2017-18367
Description
From CVE.org
libseccomp-golang 0.9.0 and earlier incorrectly generates BPFs that OR multiple arguments rather than ANDing them. A process running under a restrictive seccomp filter that specified multiple syscall arguments could bypass intended access restrictions by specifying a single matching argument.
Statement
This issue may affect OpenShift Container Platform 3.x and 4.x if you are providing a custom Seccomp profile using Security Context Constraints [1]. The custom Seccomp profile would need to specify multiple arguments, such as below, from [2].
{ "names": [ "socketcall" ], "action": "SCMP_ACT_ALLOW", "args": [ { "index": 0, "value": 1, "valueTwo": 0, "op": "SCMP_CMP_EQ" }, { "index": 1, "value": 1, "valueTwo": 0, "op": "SCMP_CMP_EQ" } ], "comment": "", "includes": {}, "excludes": {} },
If such a profile was used the arguments could be combined as an OR rule, not AND, as the user might expect from Seccomp.
[2] https://github.com/moby/moby/issues/32714#issuecomment-295532163
Common Vulnerability Scoring System (CVSS) Score Details
Info alert:Important note
CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).
CVSS v3 Score Breakdown
| Red Hat | NVD | cve.org | |
|---|---|---|---|
| Base Score | 6.5 | 7.5 | N/A |
| Attack Vector | Network | Network | N/A |
| Attack Complexity | Low | Low | N/A |
| Privileges Required | Low | None | N/A |
| User Interaction | None | None | N/A |
| Scope | Unchanged | Unchanged | N/A |
| Confidentiality | None | None | N/A |
| Integrity Impact | High | High | N/A |
| Availability Impact | None | None | N/A |
Vector
Red Hat: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N
NVD: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Understanding the Weakness (CWE)
Access Control
Technical Impact: Bypass Protection Mechanism
Frequently Asked Questions
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