CVE-2011-3624

Various methods in WEBrick::HTTPRequest in Ruby 1.9.2 and 1.8.7 and earlier do not validate the X-Forwarded-For, X-Forwarded-Host and X-Forwarded-Server headers in requests, which might allow remote attackers to inject arbitrary text into log files or bypass intended address parsing via a crafted header.

Published: 2019-11-26 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2011-3624 is rated Moderate Risk (46.7/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.52%). 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-2011-3624

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 0.93% 1.52% +0.60%
2 2025-12-28 0.45% 0.93% +0.47%
3 2025-12-27 — 0.45% —

Full EPSS history (14 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2011-3624

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/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: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:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 1.4 [email protected]
5.0 2.0 MEDIUM
AV:N/AC:L/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:L)
Exploitation conditions are straightforward and predictable.
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.
 10.0 2.9 [email protected]

Weakness enumeration for CVE-2011-3624

OS Trackers for CVE-2011-3624

vendor priority summary link
redhat low — https://access.redhat.com/security/cve/CVE-2011-3624
ubuntu low CVE-2011-3624 low priority: Ubuntu including 1 source packages (ruby1.9.1), 21 status rows across 21 suites (artful, bionic, cosmic, disco, hardy, lucid, maverick, natty, oneiric, precise, quantal, raring, saucy, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): DNE 10, ignored 10, not-affected 1. https://ubuntu.com/security/CVE-2011-3624

Affected software / configurations for CVE-2011-3624

Vendor Product Version Raw CPE
ruby-lang ruby 1.8.7 cpe:2.3:a:ruby-lang:ruby:1.8.7:*:*:*:*:*:*:*
ruby-lang ruby 1.9.2 cpe:2.3:a:ruby-lang:ruby:1.9.2:*:*:*:*:*:*:*

References for CVE-2011-3624

cvelogic Threat Intelligence