CVE-2016-4450 [High] | Denial of Service in Ubuntu Linux

os/unix/ngx_files.c in nginx before 1.10.1 and 1.11.x before 1.11.1 allows remote attackers to cause a denial of service (NULL pointer dereference and worker process crash) via a crafted request, involving writing a client request body to a temporary file.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-05-31	3.47%	3.59%	+0.12%
2	2026-05-05	4.02%	3.47%	-0.55%
3	2026-03-04	—	4.02%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-05-31

3.47%

3.59%

+0.12%

2026-05-05

4.02%

3.47%

-0.55%

2026-03-04

—

4.02%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
7.5	3.1	HIGH	`CVSS:3.1/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]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

7.5

3.1

HIGH

CVSS:3.1/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]

OS Trackers for CVE-2016-4450

vendor	priority	summary	link
`debian`	not yet assigned	CVE-2016-4450 not yet assigned priority: Debian including 1 source packages (nginx), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2016-4450
`gentoo`	normal	CVE-2016-4450: 1 GLSA(s) (201606-06), 1 atom(s) (www-servers/nginx); latest impact normal.	https://bugs.gentoo.org/buglist.cgi?quicksearch=CVE-2016-4450
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2016-4450
`suse`	medium	CVE-2016-4450 severity moderate: SUSE including 18 source package names (nginx, nginx-1.0-1.0.15-0.34.1, …), 23 product×package rows across 16 product lines (SUSE Lifecycle Management Server 1.3, SUSE Linux Enterprise High Performance Computing 15-LTSS, … (16 product lines)): Fixed 19, Known Not Affected 4.	https://www.suse.com/security/cve/CVE-2016-4450/
`ubuntu`	medium	CVE-2016-4450 medium priority: Ubuntu including 1 source packages (nginx), 7 status rows across 7 suites (precise, trusty, upstream, wily, xenial, yakkety, zesty): released 6, ignored 1.	https://ubuntu.com/security/CVE-2016-4450

Affected software / configurations for CVE-2016-4450

Vendor	Product	Version	Raw CPE
canonical	ubuntu_linux	14.04	cpe:2.3:o:canonical:ubuntu_linux:14.04::::esm:::
canonical	ubuntu_linux	15.10	cpe:2.3:o:canonical:ubuntu_linux:15.10:::::::*
canonical	ubuntu_linux	16.04	cpe:2.3:o:canonical:ubuntu_linux:16.04::::lts:::
f5	nginx	>= 1.3.9, < 1.10.1	cpe:2.3:a:f5:nginx::::::::
f5	nginx	1.11.0	cpe:2.3:a:f5:nginx:1.11.0:::::::*
debian	debian_linux	8.0	cpe:2.3:o:debian:debian_linux:8.0:::::::*

References for CVE-2016-4450

URL	Tags
http://mailman.nginx.org/pipermail/nginx-announce/2016/000179.html	Vendor Advisory
http://www.debian.org/security/2016/dsa-3592	Third Party Advisory
http://www.securityfocus.com/bid/90967	Third Party Advisory VDB Entry
http://www.securitytracker.com/id/1036019	Third Party Advisory VDB Entry
http://www.ubuntu.com/usn/USN-2991-1	Third Party Advisory
https://access.redhat.com/errata/RHSA-2016:1425	Third Party Advisory
https://security.gentoo.org/glsa/201606-06	Third Party Advisory

URL

CVE-2016-4450

Exploit prediction scoring system (EPSS) score for CVE-2016-4450

Common vulnerability scoring system (CVSS) metrics for CVE-2016-4450

Weakness enumeration for CVE-2016-4450

OS Trackers for CVE-2016-4450

Affected software / configurations for CVE-2016-4450

References for CVE-2016-4450