>
Apache

CVE-2021-41773

actively exploited
malware scan detection code search

A flaw was found in a change made to path normalization in Apache HTTP Server 2.4.49. An attacker could use a path traversal attack to map URLs to files outside the directories configured by Alias-like directives. If files outside of these directories are not protected by the usual default configuration "require all denied", these requests can succeed. If CGI scripts are also enabled for these aliased pathes, this could allow for remote code execution. This issue is known to be exploited in the wild. This issue only affects Apache 2.4.49 and not earlier versions. The fix in Apache HTTP Server 2.4.50 was found to be incomplete, see CVE-2021-42013.

-
cvss
common vulnerability scoring system v3.1. measures intrinsic severity on a 0-10 scale.
epss 0.9439
exploitation prediction scoring system. probability this vulnerability will be exploited in the wild in the next 30 days.
kev yes
cisa known exploited vulnerabilities catalog. confirmed active exploitation.
CVSS 3.1 Common Vulnerability Scoring System v3.1
9.8 / 10
CRITICAL
exploitability
Attack Vector
Network
Attack Vector (AV:N): exploitable remotely over the network — most dangerous. no physical or adjacent access needed.
Attack Complexity
Low
Attack Complexity (AC:L): no special conditions needed. attack can be reliably reproduced.
Privileges Required
None
Privileges Required (PR:N): no authentication needed. any anonymous attacker can exploit this.
User Interaction
None
User Interaction (UI:N): no victim action needed. fully exploitable without user interaction.
impact
Scope
Unchanged
Scope (S:U): impact limited to the vulnerable component.
Confidentiality
High
Confidentiality (C:H): total information disclosure. attacker gains access to all data within the component.
Integrity
High
Integrity (I:H): complete data modification possible. attacker can modify any data.
Availability
High
Availability (A:H): total denial of service. attacker can fully shut down the resource.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
exploit detect attrib advisory media timeline
exploitation detection attribution advisories media timeline
activity density
rdintel assessment
actively exploited. patch immediately.
ransomware in use.
flagged malicious repos detected. do not execute.
detection rules available.
61 threat composite score from 15+ signals including exploitation status, epss probability, detection coverage, and community attention. 0-100 scale.

sign in to view full intelligence

pocs, detection rules, timeline, advisories, and more

sign in create account