HOMEVULNERABILITIESCVE-2016-1133
LOW

CVE-2016-1133

NVD-CWE-OtherPublished: January 16, 2016· Updated: Jun 17, 2026

3.7
CVSS v3.1

Official Description

CRLF injection vulnerability in the on_req function in lib/handler/redirect.c in H2O before 1.6.2 and 1.7.x before 1.7.0-beta3 allows remote attackers to inject arbitrary HTTP headers and conduct HTTP response splitting attacks via a crafted URI.

NVD Source

Technical Analysis

CVE-2016-1133 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.

The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.

CVSS v3.1 Vector Breakdown

Exploitability
Attack VectorNetwork
Attack ComplexityHigh
Privileges Req.None
User InteractionNone
ScopeUnchanged
Impact
ConfidentialityNone
IntegrityLow
AvailabilityNone
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

Affected Vendors & Products

dena1 product(s)
h2o
Source: NVD CPE · 2 total CPE entries

Exploit & PoC Resources

NO KNOWN EXPLOITNo public exploit confirmed at this time
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Official Patches & Advisories

All References (10)

Quick Facts

CVE IDCVE-2016-1133
CVSS Score3.7 / 10
SeverityLOW
CISA KEVNo
Affected1 vendor(s)
PublishedJan 16, 2016

Related CVEs (NVD-CWE-Other)

Recommended Actions

  • Apply vendor patches immediately
  • Monitor CVE-2016-1133 in threat intel feeds
  • Review IDS/IPS signatures for exploitation attempts
Data sourced from NVD (NIST), CISA KEV, and EPSS (FIRST). Analysis generated by CTIWATCH.COM. CVE data is provided under the NVD usage policy.