CVE-2016-1133

mediumpriority · track · 16EPSS 0.015 · 73 %ileEUUS

grimoire priorityP3 · Track

Exploitable?

—

no known exploitation

Likely / severe?

1.46% (73rd) EPSS

CVSS 4.3 · medium

Is it mine?

3 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-28

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.

cvss

Technical severity, 0–10. One row per scoring source.

4.3

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · low–medium · 3.4–4.3

v2.04.3mediumAV:N/AC:M/Au:N/C:N/I:P/A:Nprimary · NVD / NIST USexploitability 8.6 · impact 2.9

v3.03.7lowCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:Nprimary · NVD / NIST USexploitability 2.2 · impact 1.4

v3.03.4lowCVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-113USLLM-inferred

affected products (3)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
dena h2o≤ 1.6.1nvdUScpe:2.3:a:dena:h2o:*:*:*:*:*:*:*:*
dena h2o= 1.7.0nvdUScpe:2.3:a:dena:h2o:*:*:*:*:*:*:*:*

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2016-01-16modified 2026-06-17

references (15)

External citations — patches, advisories, analysis.

scry

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