CVE-2016-1000104 [High] | Input Validation Bypass in Mod Fcgid

CVE-2016-1000104 is rated High Risk (65.2/100): CVSS High severity, with medium exploitation likelihood (EPSS 2.23%). EPSS rose +1.82% over the last day, indicating growing attacker interest. High exploitation likelihood—assess exposure and prioritize remediation.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2026-06-15	0.41%	2.23%	+1.82%
2	2025-07-13	0.53%	0.41%	-0.13%
3	2025-06-19	—	0.53%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2026-06-15

0.41%

2.23%

+1.82%

2025-07-13

0.53%

0.41%

-0.13%

2025-06-19

—

0.53%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
8.8	3.1	HIGH	`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:L) A normal user session is enough; they don’t have to be admin. 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:H) Serious risk that confidential data gets exposed in a big way. Integrity (I:H) They could widely tamper with or forge data—trust in the data is badly hurt. Availability (A:H) Could take the service down hard or make it unusable for people who depend on it.	2.8	5.9	[email protected]
6.5	2.0	MEDIUM	`AV:N/AC:L/Au:S/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:S) A single authentication is required. Confidentiality impact (C:P) Partial confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:P) Partial availability impact.	8.0	6.4	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

8.8

3.1

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/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:L): A normal user session is enough; they don’t have to be admin.
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:H): Serious risk that confidential data gets exposed in a big way.
Integrity (I:H): They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H): Could take the service down hard or make it unusable for people who depend on it.

2.8

5.9

[email protected]

6.5

2.0

MEDIUM

AV:N/AC:L/Au:S/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:S): A single authentication is required.
Confidentiality impact (C:P): Partial confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:P): Partial availability impact.

8.0

6.4

[email protected]

OS Trackers for CVE-2016-1000104

vendor	priority	summary	link
`redhat`	high	—	https://access.redhat.com/security/cve/CVE-2016-1000104
`suse`	medium	CVE-2016-1000104 severity moderate: SUSE including 2 source package names (apache2-mod_fcgid-2.2-31.29.1, apache2-mod_fcgid-2.3.9-7.3), 2 product×package rows across 2 product lines (SUSE Linux Enterprise Software Development Kit 11 SP4, openSUSE Tumbleweed): Fixed 2.	https://www.suse.com/security/cve/CVE-2016-1000104/
`ubuntu`	medium	CVE-2016-1000104 medium priority: Ubuntu including 1 source packages (libapache2-mod-fcgid), 24 status rows across 24 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, precise, questing, trusty, upstream, wily, xenial, yakkety, zesty): ignored 17, needed 6, DNE 1.	https://ubuntu.com/security/CVE-2016-1000104

Affected software / configurations for CVE-2016-1000104

Vendor	Product	Version	Raw CPE
apache	mod_fcgid	<= 2016-07-07	cpe:2.3:a:apache:mod_fcgid::::::::
opensuse	leap	42.1	cpe:2.3:o:opensuse:leap:42.1:::::::*
opensuse	opensuse	13.2	cpe:2.3:o:opensuse:opensuse:13.2:::::::*

References for CVE-2016-1000104

URL	Tags
http://lists.opensuse.org/opensuse-updates/2016-08/msg00084.html	Mailing List Third Party Advisory
http://www.openwall.com/lists/oss-security/2016/07/18/6
http://www.securityfocus.com/bid/91822
https://www.tenable.com/security/tns-2017-04

URL

CVE-2016-1000104

Exploit prediction scoring system (EPSS) score for CVE-2016-1000104

Common vulnerability scoring system (CVSS) metrics for CVE-2016-1000104

Weakness enumeration for CVE-2016-1000104

OS Trackers for CVE-2016-1000104

Affected software / configurations for CVE-2016-1000104

References for CVE-2016-1000104