zsh: null-pointer deref when using ${(PA)...} on an empty array result
Published Feb 27, 2018
9.8
CRITICALCVSS 3.0
EPSS 2.54%
Description
In subst.c in zsh through 5.4.2, there is a NULL pointer dereference when using ${(PA)...} on an empty array result.
Affected products
No data.
Configuration 2
- 17.10
No data.
Red Hat Enterprise Linux 5
zsh
Not affected
Red Hat Enterprise Linux 6
zsh
Not affected
Red Hat Enterprise Linux 7
zsh
Not affected
Red Hat Enterprise Linux 8
zsh
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 5 | zsh | Not affected | n/a |
| Red Hat Enterprise Linux 6 | zsh | Not affected | n/a |
| Red Hat Enterprise Linux 7 | zsh | Not affected | n/a |
| Red Hat Enterprise Linux 8 | zsh | Not affected | n/a |
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.0/AV:L/AC:L/PR:L/UI:R/S:U/C:N/I:N/A:L
AV:N/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 v2
- EPSS v3
- EPSS v5
Percentile over time
- EPSS v1
- EPSS v2
- EPSS v3
- EPSS v5
Table of values (14 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 2.54% (0.02543) | 84.43th | v5 (v2026.06.15) |
| Jun 15, 2026 | 2.63% (0.02633) | 83.50th | v5 (v2026.06.15) |
| Jul 20, 2024 | 0.32% (0.00316) | 70.65th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.32% (0.00316) | 69.55th | v3 (v2023.03.01) |
| Jul 21, 2023 | 0.32% (0.00316) | 66.35th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.30% (0.00304) | 64.94th | v3 (v2023.03.01) |
| Mar 6, 2023 | 0.95% (0.00954) | 36.37th | v2 (v2022.01.01) |
| Sep 2, 2022 | 0.95% (0.00954) | 34.50th | v2 (v2022.01.01) |
| Apr 1, 2022 | 0.95% (0.00954) | 32.50th | v2 (v2022.01.01) |
| Feb 4, 2022 | 0.95% (0.00954) | 16.28th | v2 (v2022.01.01) |
| Feb 3, 2022 | 0.83% (0.00833) | 24.58th | v1 |
| Jan 6, 2022 | 0.83% (0.00833) | 23.96th | v1 |
| Sep 1, 2021 | 0.83% (0.00833) | 57.50th | v1 |
| Apr 14, 2021 | 0.83% (0.00833) | 0.00th | v1 |
References (7)
- https://access.redhat.com/security/cve/CVE-2018-7548 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1549841 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2018-7548
- https://security.gentoo.org/glsa/201805-10 vendor-advisoryx_refsource_GENTOOThird Party Advisory
- https://sourceforge.net/p/zsh/code/ci/110b13e1090bc31ac1352b28adc2d02b6d25a102 x_refsource_MISCPatchThird Party Advisory
- https://usn.ubuntu.com/3593-1/ vendor-advisoryx_refsource_UBUNTUThird Party Advisory
- https://www.cve.org/CVERecord?id=CVE-2018-7548
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2018-7548 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1549841 | Issue Tracking | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-7548 | ||
| https://security.gentoo.org/glsa/201805-10 | vendor-advisoryx_refsource_GENTOOThird Party Advisory | |
| https://sourceforge.net/p/zsh/code/ci/110b13e1090bc31ac1352b28adc2d02b6d25a102 | x_refsource_MISCPatchThird Party Advisory | |
| https://usn.ubuntu.com/3593-1/ | vendor-advisoryx_refsource_UBUNTUThird Party Advisory | |
| https://www.cve.org/CVERecord?id=CVE-2018-7548 |
Change history (0)
No recorded changes yet.