CVE-2016-1951

Multiple integer overflows in io/prprf.c in Mozilla Netscape Portable Runtime (NSPR) before 4.12 allow remote attackers to cause a denial of service (buffer overflow) or possibly have unspecified other impact via a long string to a PR_*printf function.

Published: 2016-08-07 Last update: 2026-05-06 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2016-1951 is rated High Risk (65.8/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.74%). EPSS rose +1.95% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize 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-2016-1951

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 0.79% 2.74% +1.95%
2 2025-09-05 0.74% 0.79% +0.04%
3 2025-08-23 — 0.74% —

Full EPSS history (9 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2016-1951

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.6 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/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:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 3.9 4.7 [email protected]
7.5 2.0 HIGH
AV:N/AC:L/Au:N/C:P/I:P/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:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 10.0 6.4 [email protected]

Weakness enumeration for CVE-2016-1951

OS Trackers for CVE-2016-1951

vendor priority summary link
debian not yet assigned CVE-2016-1951 not yet assigned priority: Debian including 3 source packages (firefox, firefox-esr, nspr), 11 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 11. https://security-tracker.debian.org/tracker/CVE-2016-1951
redhat medium — https://access.redhat.com/security/cve/CVE-2016-1951
suse medium CVE-2016-1951 severity moderate: SUSE including 3 source package names (mozilla-nspr, mozilla-nspr-32bit, mozilla-nspr-devel), 21 product×package rows across 12 product lines (SUSE Linux Enterprise Desktop 12, SUSE Linux Enterprise Desktop 12 SP1, … (12 product lines)): Known Not Affected 21. https://www.suse.com/security/cve/CVE-2016-1951/
ubuntu medium CVE-2016-1951 medium priority: Ubuntu including 3 source packages (firefox, nspr, thunderbird), 21 status rows across 7 suites (precise, trusty, upstream, wily, xenial, yakkety, zesty): released 12, not-affected 8, DNE 1. https://ubuntu.com/security/CVE-2016-1951

Affected software / configurations for CVE-2016-1951

Vendor Product Version Raw CPE
mozilla netscape_portable_runtime <= 4.11 cpe:2.3:a:mozilla:netscape_portable_runtime:*:*:*:*:*:*:*:*

References for CVE-2016-1951

cvelogic Threat Intelligence