AppArmor cupsd Sandbox Bypass Due to Use of Hard Links
Published Aug 10, 2018
8.8
HIGHCVSS 3.0
EPSS 0.39%
Description
The CUPS AppArmor profile incorrectly confined the dnssd backend due to use of hard links. A local attacker could possibly use this issue to escape confinement. This flaw affects versions prior to 2.2.7-1ubuntu2.1 in Ubuntu 18.04 LTS, prior to 2.2.4-7ubuntu3.1 in Ubuntu 17.10, prior to 2.1.3-4ubuntu0.5 in Ubuntu 16.04 LTS, and prior to 1.7.2-0ubuntu1.10 in Ubuntu 14.04 LTS.
Affected products
- Vendor n/a Product Cups Defaultn/a
- Version unspecifiedStatusaffectedConstraints<1.7.2-0ubuntu1.10
- Version unspecifiedStatusaffectedConstraints<2.1.3-4ubuntu0.5
- Version unspecifiedStatusaffectedConstraints<2.2.4-7ubuntu3.1
- Version unspecifiedStatusaffectedConstraints<2.2.7-1ubuntu2.1
- Version
Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).
| Vendor | Product | Default status | Versions | |||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n/a | Cups | n/a |
|
- n/a
- 14.04
- 16.04
- 17.10
- 18.04
- 8.0
- 9.0
No data.
Red Hat Enterprise Linux 5
cups
Not affected
Red Hat Enterprise Linux 6
cups
Not affected
Red Hat Enterprise Linux 7
cups
Not affected
Red Hat Enterprise Linux 8
cups
Not affected
Red Hat Virtualization 4
cups
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | cups | Not affected | n/a |
| Red Hat Enterprise Linux 6 | cups | Not affected | n/a |
| Red Hat Enterprise Linux 7 | cups | Not affected | n/a |
| Red Hat Enterprise Linux 8 | cups | Not affected | n/a |
| Red Hat Virtualization 4 | cups | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
This issue did not affect the versions of cups as shipped with Red Hat Enterprise Linux as they did not include support for AppArmor.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H
AV:L/AC:L/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
Table of values (8 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.39% (0.00385) | 30.09th | v5 (v2026.06.15) |
| Sep 20, 2026 | 0.39% (0.00385) | 32.38th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.04% (0.00042) | 5.06th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.04% (0.00042) | 5.63th | v3 (v2023.03.01) |
| Mar 6, 2023 | 0.95% (0.00950) | 32.28th | v2 (v2022.01.01) |
| Feb 4, 2022 | 0.95% (0.00950) | 13.46th | v2 (v2022.01.01) |
| Feb 3, 2022 | 0.56% (0.00555) | 12.81th | v5 (v2026.06.15) |
| Apr 14, 2021 | 0.56% (0.00555) | 0.00th | v1 |
References (8)
- https://access.redhat.com/security/cve/CVE-2018-6553 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1607285 Issue Tracking
- https://lists.debian.org/debian-lts-announce/2018/07/msg00014.html mailing-listx_refsource_MLISTIssue TrackingMailing ListThird Party Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2018-6553
- https://security.gentoo.org/glsa/201908-08 vendor-advisoryx_refsource_GENTOO
- https://usn.ubuntu.com/usn/usn-3713-1 vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2018-6553
- https://www.debian.org/security/2018/dsa-4243 vendor-advisoryx_refsource_DEBIANThird Party Advisory
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2018-6553 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1607285 | Issue Tracking | |
| https://lists.debian.org/debian-lts-announce/2018/07/msg00014.html | mailing-listx_refsource_MLISTIssue TrackingMailing ListThird Party Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-6553 | ||
| https://security.gentoo.org/glsa/201908-08 | vendor-advisoryx_refsource_GENTOO | |
| https://usn.ubuntu.com/usn/usn-3713-1 | vendor-advisoryx_refsource_UBUNTUThird Party Advisory | |
| https://www.cve.org/CVERecord?id=CVE-2018-6553 | ||
| https://www.debian.org/security/2018/dsa-4243 | vendor-advisoryx_refsource_DEBIANThird Party Advisory |
Change history (0)
No recorded changes yet.