Bug 1706826 (CVE-2017-18367) - CVE-2017-18367 libseccomp-golang: mishandling of multiple argument rules leading to a bypass of intended access restrictions
Summary: CVE-2017-18367 libseccomp-golang: mishandling of multiple argument rules lead...
Keywords:
Status: CLOSED ERRATA
Alias: CVE-2017-18367
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Red Hat Product Security
QA Contact:
URL:
Whiteboard:
Depends On: 1706828 1706829 1728130 1728131 1779016 1779017 1779018 1779019 1779020
Blocks: 1706830
TreeView+ depends on / blocked
 
Reported: 2019-05-06 11:11 UTC by Marian Rehak
Modified: 2021-02-16 21:58 UTC (History)
18 users (show)

Fixed In Version: libseccomp-golang 0.9.1
Doc Type: If docs needed, set a value
Doc Text:
Clone Of:
Environment:
Last Closed: 2019-12-17 08:09:24 UTC


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Links
System ID Private Priority Status Summary Last Updated
Red Hat Product Errata RHSA-2019:4087 0 None None None 2019-12-17 02:17:25 UTC
Red Hat Product Errata RHSA-2019:4090 0 None None None 2019-12-17 07:40:05 UTC
Red Hat Product Errata RHSA-2020:2479 0 None None None 2020-06-18 21:11:28 UTC

Description Marian Rehak 2019-05-06 11:11:22 UTC
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.

External References:
https://www.openwall.com/lists/oss-security/2019/04/25/6

Upstream Bug:
https://github.com/seccomp/libseccomp-golang/issues/22

Upstream Patch:
https://github.com/seccomp/libseccomp-golang/commit/06e7a29f36a34b8cf419aeb87b979ee508e58f9e

Comment 1 Marian Rehak 2019-05-06 11:15:19 UTC
Created golang-github-seccomp-libseccomp-golang tracking bugs for this issue:

Affects: epel-6 [bug 1706829]
Affects: fedora-all [bug 1706828]

Comment 2 Jason Shepherd 2019-07-09 05:48:39 UTC
This issue affects

Comment 9 errata-xmlrpc 2019-12-17 02:17:22 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.1

Via RHSA-2019:4087 https://access.redhat.com/errata/RHSA-2019:4087

Comment 10 errata-xmlrpc 2019-12-17 07:40:03 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 4.1

Via RHSA-2019:4090 https://access.redhat.com/errata/RHSA-2019:4090

Comment 11 Product Security DevOps Team 2019-12-17 08:09:24 UTC
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2017-18367

Comment 12 Mauro Matteo Cascella 2020-02-21 15:51:07 UTC
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.

[1] https://docs.openshift.com/container-platform/4.1/authentication/managing-security-context-constraints.html

[2] https://github.com/moby/moby/issues/32714#issuecomment-295532163

Comment 13 errata-xmlrpc 2020-06-18 21:11:26 UTC
This issue has been addressed in the following products:

  Red Hat OpenShift Container Platform 3.11

Via RHSA-2020:2479 https://access.redhat.com/errata/RHSA-2020:2479


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