CVE-2014-6393 [Medium] | XSS in Express

The Express web framework before 3.11 and 4.x before 4.5 for Node.js does not provide a charset field in HTTP Content-Type headers in 400 level responses, which might allow remote attackers to conduct cross-site scripting (XSS) attacks via characters in a non-standard encoding.

#	Date	Old EPSS score	New EPSS score	Delta (New - Old)
1	2025-03-30	0.40%	0.29%	-0.11%
2	2025-03-29	0.31%	0.40%	+0.09%
3	2025-03-17	—	0.31%	—

Date

Old EPSS score

New EPSS score

Delta (New - Old)

2025-03-30

0.40%

0.29%

-0.11%

2025-03-29

0.31%

0.40%

+0.09%

2025-03-17

—

0.31%

—

Base score	Version	Severity	Vector	Exploitability	Impact	Score source
6.1	3.0	MEDIUM	`CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N` 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:R) A real person has to do something—click, install, enable—otherwise it doesn’t land. Scope (S:C) Breaking this can reach past the original component and bite other resources—bigger blast radius. 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:N) Service keeps running; no real outage angle.	2.8	2.7	[email protected]
4.3	2.0	MEDIUM	`AV:N/AC:M/Au:N/C:N/I:P/A:N` Click to expand Access vector (AV:N) Can be exploited remotely over network reachability. Access complexity (AC:M) Exploitation needs some favorable conditions, but not exceptional ones. Authentication (AU:N) No authentication is required. Confidentiality impact (C:N) No confidentiality impact. Integrity impact (I:P) Partial integrity impact. Availability impact (A:N) No availability impact.	8.6	2.9	[email protected]

Base score

Version

Severity

Vector

Exploitability

Impact

Score source

6.1

3.0

MEDIUM

CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N 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:R): A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C): Breaking this can reach past the original component and bite other resources—bigger blast radius.
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:N): Service keeps running; no real outage angle.

2.8

2.7

[email protected]

4.3

2.0

MEDIUM

AV:N/AC:M/Au:N/C:N/I:P/A:N Click to expand

Access vector (AV:N): Can be exploited remotely over network reachability.
Access complexity (AC:M): Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N): No authentication is required.
Confidentiality impact (C:N): No confidentiality impact.
Integrity impact (I:P): Partial integrity impact.
Availability impact (A:N): No availability impact.

8.6

2.9

[email protected]

OS Trackers for CVE-2014-6393

vendor	priority	summary	link
`debian`	unimportant	CVE-2014-6393 unimportant priority: Debian including 1 source packages (node-express), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5.	https://security-tracker.debian.org/tracker/CVE-2014-6393
`redhat`	medium	—	https://access.redhat.com/security/cve/CVE-2014-6393
`ubuntu`	medium	CVE-2014-6393 medium priority: Ubuntu including 1 source packages (node-express), 27 status rows across 27 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lucid, lunar, mantic, noble, oracular, plucky, precise, questing, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): released 14, ignored 7, DNE 3, needed 2, needs-triage 1.	https://ubuntu.com/security/CVE-2014-6393

Affected software / configurations for CVE-2014-6393

Vendor	Product	Version	Raw CPE
openjsf	express	<= 3.10.5	cpe:2.3:a:openjsf:express::::::::
openjsf	express	4.0.0	cpe:2.3:a:openjsf:express:4.0.0:::::::*
openjsf	express	4.1.0	cpe:2.3:a:openjsf:express:4.1.0:::::::*
openjsf	express	4.1.1	cpe:2.3:a:openjsf:express:4.1.1:::::::*
openjsf	express	4.1.2	cpe:2.3:a:openjsf:express:4.1.2:::::::*
openjsf	express	4.2.0	cpe:2.3:a:openjsf:express:4.2.0:::::::*
openjsf	express	4.3.0	cpe:2.3:a:openjsf:express:4.3.0:::::::*
openjsf	express	4.3.1	cpe:2.3:a:openjsf:express:4.3.1:::::::*
openjsf	express	4.3.2	cpe:2.3:a:openjsf:express:4.3.2:::::::*
openjsf	express	4.4.0	cpe:2.3:a:openjsf:express:4.4.0:::::::*
openjsf	express	4.4.1	cpe:2.3:a:openjsf:express:4.4.1:::::::*
openjsf	express	4.4.2	cpe:2.3:a:openjsf:express:4.4.2:::::::*
openjsf	express	4.4.3	cpe:2.3:a:openjsf:express:4.4.3:::::::*
openjsf	express	4.4.4	cpe:2.3:a:openjsf:express:4.4.4:::::::*
openjsf	express	4.4.5	cpe:2.3:a:openjsf:express:4.4.5:::::::*

References for CVE-2014-6393

URL	Tags
https://bugzilla.redhat.com/show_bug.cgi?id=1203190	Issue Tracking Third Party Advisory VDB Entry
https://nodesecurity.io/advisories/express-no-charset-in-content-type-header	Third Party Advisory

URL

CVE-2014-6393

Exploit prediction scoring system (EPSS) score for CVE-2014-6393

Common vulnerability scoring system (CVSS) metrics for CVE-2014-6393

Weakness enumeration for CVE-2014-6393

GitHub Security Advisory for CVE-2014-6393

OS Trackers for CVE-2014-6393

Affected software / configurations for CVE-2014-6393

References for CVE-2014-6393