CVE-2017-7502

Null pointer dereference vulnerability in NSS since 3.24.0 was found when server receives empty SSLv2 messages resulting into denial of service by remote attacker.

Published: 2017-05-30 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2017-7502 is rated Moderate Risk (64.3/100): CVSS High severity, with medium exploitation likelihood (EPSS 4.30%). EPSS rose +2.85% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2017-7502

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 1.45% 4.30% +2.85%
2 2026-05-15 2.10% 1.45% -0.65%
3 2026-02-19 — 2.10% —

Full EPSS history (28 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2017-7502

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2017-7502

OS Trackers for CVE-2017-7502

vendor priority summary link
debian not yet assigned CVE-2017-7502 not yet assigned priority: Debian including 1 source packages (nss), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2017-7502
redhat high — https://access.redhat.com/security/cve/CVE-2017-7502
suse high CVE-2017-7502 severity important: SUSE including 21 source package names (libfreebl3, libfreebl3-32bit, …), 92 product×package rows across 13 product lines (SUSE Liberty Linux 7, SUSE Linux Enterprise Desktop 12 SP1, … (13 product lines)): Known Not Affected 87, Fixed 5. https://www.suse.com/security/cve/CVE-2017-7502/
ubuntu medium CVE-2017-7502 medium priority: Ubuntu including 1 source packages (nss), 5 status rows across 5 suites (trusty, upstream, xenial, yakkety, zesty): released 4, needs-triage 1. https://ubuntu.com/security/CVE-2017-7502

Affected software / configurations for CVE-2017-7502

Vendor Product Version Raw CPE
mozilla network_security_services 3.24.0 cpe:2.3:a:mozilla:network_security_services:3.24.0:*:*:*:*:*:*:*
mozilla network_security_services 3.25.0 cpe:2.3:a:mozilla:network_security_services:3.25.0:*:*:*:*:*:*:*
mozilla network_security_services 3.25.1 cpe:2.3:a:mozilla:network_security_services:3.25.1:*:*:*:*:*:*:*
mozilla network_security_services 3.26.0 cpe:2.3:a:mozilla:network_security_services:3.26.0:*:*:*:*:*:*:*
mozilla network_security_services 3.26.2 cpe:2.3:a:mozilla:network_security_services:3.26.2:*:*:*:*:*:*:*
mozilla network_security_services 3.27.0 cpe:2.3:a:mozilla:network_security_services:3.27.0:*:*:*:*:*:*:*
mozilla network_security_services 3.27.1 cpe:2.3:a:mozilla:network_security_services:3.27.1:*:*:*:*:*:*:*
mozilla network_security_services 3.27.2 cpe:2.3:a:mozilla:network_security_services:3.27.2:*:*:*:*:*:*:*
mozilla network_security_services 3.28.0 cpe:2.3:a:mozilla:network_security_services:3.28.0:*:*:*:*:*:*:*
mozilla network_security_services 3.28.1 cpe:2.3:a:mozilla:network_security_services:3.28.1:*:*:*:*:*:*:*
mozilla network_security_services 3.28.2 cpe:2.3:a:mozilla:network_security_services:3.28.2:*:*:*:*:*:*:*
mozilla network_security_services 3.28.3 cpe:2.3:a:mozilla:network_security_services:3.28.3:*:*:*:*:*:*:*
mozilla network_security_services 3.29.0 cpe:2.3:a:mozilla:network_security_services:3.29.0:*:*:*:*:*:*:*
mozilla network_security_services 3.29.1 cpe:2.3:a:mozilla:network_security_services:3.29.1:*:*:*:*:*:*:*
mozilla network_security_services 3.29.2 cpe:2.3:a:mozilla:network_security_services:3.29.2:*:*:*:*:*:*:*
mozilla network_security_services 3.29.3 cpe:2.3:a:mozilla:network_security_services:3.29.3:*:*:*:*:*:*:*
mozilla network_security_services 3.30.0 cpe:2.3:a:mozilla:network_security_services:3.30.0:*:*:*:*:*:*:*
mozilla network_security_services 3.30.1 cpe:2.3:a:mozilla:network_security_services:3.30.1:*:*:*:*:*:*:*

References for CVE-2017-7502

cvelogic Threat Intelligence