Lighttpd
CVE-2022-41556
HIGH
Vulnerability Assessment
| Weakness |
CWE
ASVS 5.0
V15 - Secure Coding and Architecture Resource cleanup, leak prevention
|
| Impact | CVSS score of 7.5 (HIGH). Attack characteristics: network attack vector, low complexity, no privileges required, no user interaction not required. Public proof-of-concept exploit code is available. |
| Exploit ScenarioDerived | A remote attacker could exhaust available memory leading to denial of service by sending crafted requests to the affected application. No authentication is required to exploit this vulnerability. |
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Alert meAnalysisAI
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. Rated high severity (CVSS 7.5), this vulnerability is remotely exploitable, no authentication required, low attack complexity. Public exploit code available.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Ensure all allocated memory is properly freed. Use RAII patterns or garbage-collected languages.
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Technical ContextAI · show details
This vulnerability is classified as Memory Leak (CWE-401), which allows attackers to exhaust available memory leading to denial of service. 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. Affected products include: Lighttpd, Fedoraproject Fedora. Version information: through 1.4.66.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
DescriptionNVD
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.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
VulDB
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)NVD
SQL injection vulnerability in mod_mysql_vhost.c in lighttpd before 1.4.35 allows remote attackers to execute arbitrary
Multiple directory traversal vulnerabilities in (1) mod_evhost and (2) mod_simple_vhost in lighttpd before 1.4.35 allow
The http_request_split_value function in request.c in lighttpd before 1.4.32 allows remote attackers to cause a denial o
mod_auth in lighttpd before 1.4.36 allows remote attackers to inject arbitrary log entries via a basic HTTP authenticati
lighttpd before 1.4.54 has a signed integer overflow, which might allow remote attackers to cause a denial of service (a
lighttpd before 1.4.34, when SNI is enabled, configures weak SSL ciphers, which makes it easier for remote attackers to
In lighttpd 1.4.65, mod_wstunnel does not initialize a handler function pointer if an invalid HTTP request (websocket ha
Lighttpd 1.4.56 through 1.4.58 allows a remote attacker to cause a denial of service (CPU consumption from stuck connect
An issue was discovered in mod_alias_physical_handler in mod_alias.c in lighttpd before 1.4.50. Rated high severity (CVS
lighttpd before 1.4.33 does not check the return value of the (1) setuid, (2) setgid, or (3) setgroups functions, which
lighttpd1.4.80 incorrectly merged trailer fields into headers after http request parsing. Rated medium severity (CVSS 6.
Use-after-free vulnerability in lighttpd before 1.4.33 allows remote attackers to cause a denial of service (segmentatio
Exploit-DB