CVE-2022-41556

HIGH
Published Oct 6, 20223y ago · Modified Jun 17, 20261w ago
7.5 CVSS 3.1
High
Find Similar
Published Oct 6, 2022 3y ago
Last Modified Jun 17, 2026 1w ago

Description

A resource leak in gw_backend.c in lighttpd 1.4.56 through 1.4.66 could lead to a denial of service (connection-slot exhaustion) after a large amount of anomalous TCP behavior by clients. It is related to RDHUP mishandling in certain HTTP/1.1 chunked situations. Use of mod_fastcgi is, for example, affected. This is fixed in 1.4.67.

CVSS Details

Base Score
7.5
Exploitability
3.9
Impact
3.6
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality None
Integrity None
Availability High

Threat Intelligence

No active exploitation signals — not in CISA KEV and no EPSS score yet.

Exploit & Patch Status
Public Exploit Known
Patch Available

Weaknesses 1

CWE-401

Affected Products 2

VendorProductVersionRange
lighttpdlighttpd*≥1.4.56  –  <1.4.67
fedoraprojectfedora35any

References 5

  • git.lighttpd.net https://git.lighttpd.net/lighttpd/lighttpd1.4/commit/b18de6f9264f914f7bf493abd3b6059343548e50
    PatchThird Party Advisory
  • github.com https://github.com/lighttpd/lighttpd1.4/compare/lighttpd-1.4.66...lighttpd-1.4.67
    Third Party Advisory
  • github.com https://github.com/lighttpd/lighttpd1.4/pull/115
    ExploitIssue TrackingThird Party Advisory
  • lists.fedoraproject.org https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/OVOSBSCMLGCHH2Z74H64ZWVDFJFQTBC2/
  • security.gentoo.org https://security.gentoo.org/glsa/202210-12
    Third Party Advisory

Remediation

  • git.lighttpd.net https://git.lighttpd.net/lighttpd/lighttpd1.4/commit/b18de6f9264f914f7bf493abd3b6059343548e50
    PatchThird Party Advisory