High severity · published Mar 23, 2022
CVE-2021-44040
Improper Input Validation vulnerability in request line parsing of Apache Traffic Server allows an attacker to send invalid requests
7.5
CVSS
2%
EPSS
No
On KEV
Description
Improper Input Validation vulnerability in request line parsing of Apache Traffic Server allows an attacker to send invalid requests. This issue affects Apache Traffic Server 8.0.0 to 8.1.3 and 9.0.0 to 9.1.1.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
High
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.0% · higher than 81% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
10.0; 11.0 · source: NVD
TS
Traffic Server · Apache
8.0.0 through 8.1.3; 9.0.0 through 9.1.1 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-44040
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-44040
Mailing List
https://lists.apache.org/thread/zblwzcfs9ryhwjr89wz4osw55pxm6dx6
Third Party Advisory
https://www.debian.org/security/2022/dsa-5153
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10.0
CVE-2026-57834
Apache Traffic Server: Malformed chunked message body allows request smuggling
9.8
CVE-2026-58185
Apache Traffic Server: Use-after-free in the intercept plugin
9.8
CVE-2026-58179
Apache Traffic Server: regex_remap plugin overflows the stack from attacker input