nss: NULL pointer dereference in several CMS functions resulting in a denial of service
Published Oct 22, 2020
6.5
MEDIUMCVSS 3.1
EPSS 1.97%
Description
In Network Security Services (NSS) before 3.36.7 and before 3.41.1, a malformed signature can cause a crash due to a null dereference, resulting in a Denial of Service.
Affected products
-
- Version unspecifiedStatusaffectedConstraints<3.36.7
- Version unspecifiedStatusaffectedConstraints<3.41.1
- Version
Configuration 1
- < 3.36.7
- ≥ 3.41 · < 3.41.1
Configuration 2
- < 2.14.0
Running on/with
- n/a
Configuration 3
- < 2.14.0
Running on/with
- n/a
Configuration 4
- < 2.14.0
Running on/with
- n/a
Configuration 5
- < 2.14.0
Running on/with
- n/a
Configuration 6
- < 2.14.0
Running on/with
- n/a
Configuration 7
- < 2.14.0
Running on/with
- n/a
Configuration 8
- < 2.14.0
Running on/with
- n/a
Configuration 9
- < 2.14.0
Running on/with
- n/a
No data.
Red Hat Enterprise Linux 8
nspr-0:4.21.0-2.el8_0
Fixed · RHSA-2019:1951
Red Hat Enterprise Linux 8
nss-0:3.44.0-7.el8_0
Fixed · RHSA-2019:1951
Red Hat Enterprise Linux 5
nss
Will not fix
Red Hat Enterprise Linux 6
nss
Will not fix
Red Hat Enterprise Linux 7
nss
Will not fix
Red Hat Enterprise Linux 8
mingw-nss
Will not fix
Red Hat Virtualization 4
redhat-virtualization-host
Will not fix
Red Hat Virtualization 4
rhvm-appliance
Will not fix
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 8 | nspr-0:4.21.0-2.el8_0 | Fixed | RHSA-2019:1951 |
| Red Hat Enterprise Linux 8 | nss-0:3.44.0-7.el8_0 | Fixed | RHSA-2019:1951 |
| Red Hat Enterprise Linux 5 | nss | Will not fix | n/a |
| Red Hat Enterprise Linux 6 | nss | Will not fix | n/a |
| Red Hat Enterprise Linux 7 | nss | Will not fix | n/a |
| Red Hat Enterprise Linux 8 | mingw-nss | Will not fix | n/a |
| Red Hat Virtualization 4 | redhat-virtualization-host | Will not fix | n/a |
| Red Hat Virtualization 4 | rhvm-appliance | Will not fix | n/a |
No package ranges for this CVE.
Remediation
Red Hat mitigation
This issue only affects applications compiled against NSS which use CMS (Cryptographic Message Syntax) API. Other applications are not affected.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
AV:N/AC:M/Au:N/C:N/I:N/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 2, 2026.
Score over time
2021–2026- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Percentile over time
- EPSS v1
- EPSS v5
- EPSS v2
- EPSS v3
- EPSS v4
Table of values (12 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 2, 2026 | 1.97% (0.01971) | 79.72th | v5 (v2026.06.15) |
| Jun 15, 2026 | 1.96% (0.01956) | 77.61th | v5 (v2026.06.15) |
| Mar 30, 2025 | 0.43% (0.00434) | 59.90th | v4 (v2025.03.14) |
| Mar 29, 2025 | 1.64% (0.01639) | 70.45th | v4 (v2025.03.14) |
| Mar 17, 2025 | 0.43% (0.00434) | 60.70th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.22% (0.00224) | 61.60th | v3 (v2023.03.01) |
| Sep 3, 2023 | 0.22% (0.00224) | 60.02th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.16% (0.00162) | 51.07th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.02% (0.01018) | 40.69th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.02% (0.01018) | 19.50th | v2 (v2022.01.01) |
| Feb 3, 2022 | 1.29% (0.01294) | 30.79th | v5 (v2026.06.15) |
| Apr 14, 2021 | 1.29% (0.01294) | 0.00th | v1 |
References (8)
- https://access.redhat.com/security/cve/CVE-2018-18508 Vendor Advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=1671310 Issue Tracking
- https://cert-portal.siemens.com/productcert/pdf/ssa-379803.pdf x_refsource_CONFIRMThird Party Advisory
- https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.36.7_release_notes x_refsource_MISCRelease NotesVendor Advisory
- https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.41.1_release_notes x_refsource_MISCRelease NotesVendor Advisory
- https://nvd.nist.gov/vuln/detail/CVE-2018-18508
- https://us-cert.cisa.gov/ics/advisories/icsa-21-040-04 x_refsource_MISCThird Party AdvisoryUS Government Resource
- https://www.cve.org/CVERecord?id=CVE-2018-18508
| Link | Providers | Tags |
|---|---|---|
| https://access.redhat.com/security/cve/CVE-2018-18508 | Vendor Advisory | |
| https://bugzilla.redhat.com/show_bug.cgi?id=1671310 | Issue Tracking | |
| https://cert-portal.siemens.com/productcert/pdf/ssa-379803.pdf | x_refsource_CONFIRMThird Party Advisory | |
| https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.36.7_release_notes | x_refsource_MISCRelease NotesVendor Advisory | |
| https://developer.mozilla.org/en-US/docs/Mozilla/Projects/NSS/NSS_3.41.1_release_notes | x_refsource_MISCRelease NotesVendor Advisory | |
| https://nvd.nist.gov/vuln/detail/CVE-2018-18508 | ||
| https://us-cert.cisa.gov/ics/advisories/icsa-21-040-04 | x_refsource_MISCThird Party AdvisoryUS Government Resource | |
| https://www.cve.org/CVERecord?id=CVE-2018-18508 |
Change history (0)
No recorded changes yet.