CVE-2018-11783

sslheaders plugin extracts information from the client certificate and sets headers in the request based on the configuration of the plugin. The plugin doesn't strip the headers from the request in some scenarios. This problem was discovered in versions 6.0.0 to 6.0.3, 7.0.0 to 7.1.5, and 8.0.0 to 8.0.1.

Published: 2019-03-07 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2018-11783 is rated Moderate Risk (57.5/100): CVSS High severity, with medium exploitation likelihood (EPSS 1.87%). Mandatory action: 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-2018-11783

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 1.12% 1.87% +0.74%
2 2025-12-28 0.73% 1.12% +0.39%
3 2025-12-27 0.73%

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-11783

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:H/I:N/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: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:N)
Data isn’t meaningfully altered or forged.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/Au:N/C:P/I:N/A:N 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:N)
No integrity impact.
Availability impact (A:N)
No availability impact.
10.0 2.9 [email protected]

Weakness enumeration for CVE-2018-11783

OS Trackers for CVE-2018-11783

vendor priority summary link
debian not yet assigned CVE-2018-11783 not yet assigned priority: Debian including 1 source packages (trafficserver), 3 status rows across 3 suites (bookworm, bullseye, sid): resolved 3. https://security-tracker.debian.org/tracker/CVE-2018-11783
ubuntu medium CVE-2018-11783 medium priority: Ubuntu including 1 source packages (trafficserver), 19 status rows across 19 suites (bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): not-affected 14, needs-triage 2, DNE 1, ignored 1, released 1. https://ubuntu.com/security/CVE-2018-11783

Affected software / configurations for CVE-2018-11783

Vendor Product Version Raw CPE
apache traffic_server >= 6.0.0, <= 6.0.3 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
apache traffic_server >= 7.0.0, <= 7.1.5 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*
apache traffic_server >= 8.0.0, <= 8.0.1 cpe:2.3:a:apache:traffic_server:*:*:*:*:*:*:*:*

References for CVE-2018-11783

cvelogic Threat Intelligence