CVE-2016-1133

low

Published 2016-01-16 · Modified 2026-05-06

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CVSS v3

3.7

CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS v4 NEW

—

not yet in upstream

VIR risk

3.7

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.

Predictions

Exploit likelihood

47%

Patch ETA

—

Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

Debian Fixed 2 releases

Version	Status	Fixed in
bullseye	Fixed	`0`
bookworm	Fixed	`0`

Application impact

Vendor	Product	Versions	Fixed
dena	h2o	`{"endIncluding":"1.6.1"}`
dena	h2o	`1.7.0`

References

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.