Medium severity · published Jul 12, 2021
CVE-2021-33037
Incorrect Transfer-Encoding handling with HTTP/1.0
5.3
CVSS
74.7%
EPSS
No
On KEV
Description
Apache Tomcat 10.0.0-M1 to 10.0.6, 9.0.0.M1 to 9.0.46 and 8.5.0 to 8.5.66 did not correctly parse the HTTP transfer-encoding request header in some circumstances leading to the possibility to request smuggling when used with a reverse proxy. Specifically: - Tomcat incorrectly ignored the transfer encoding header if the client declared it would only accept an HTTP/1.0 response; - Tomcat honoured the identify encoding; and - Tomcat did not ensure that, if present, the chunked encoding was the final encoding.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)74.7% · higher than 99% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
TO
Tomcat · Apache
Apache Tomcat 10 10.0.0-M1 to 10.0.6; Apache Tomcat 9 9.0.0.M1 to 9.0.46; Apache Tomcat 8 8.5.0 to 8.5.66 · source: vendor, NVD
AP
Agile Product Lifecycle Management · Oracle
9.3.6 · source: NVD
CC
Communications Cloud Native Core Policy · Oracle
1.14.0 · source: NVD
CC
Communications Cloud Native Core Service Communication Proxy · Oracle
1.14.0 · source: NVD
CD
Communications Diameter Signaling Router · Oracle
8.0.0.0 through 8.5.0.2 · source: NVD
CI
Communications Instant Messaging Server · Oracle
10.0.1.5.0 · source: NVD
CP
Communications Policy Management · Oracle
12.5.0 · source: NVD
CP
Communications Pricing Design Center · Oracle
12.0.0.3.0 · source: NVD
CS
Communications Session Report Manager · Oracle
8.0.0 through 8.2.4.0 · source: NVD
CS
Communications Session Route Manager · Oracle
8.0.0 through 8.2.4 · source: NVD
DL
Debian Linux · Debian
9.0; 10.0 · source: NVD
EO
Epolicy Orchestrator · Mcafee
before 5.10.0; 5.10.0; 5.10.0; 5.10.0; 5.10.0; 5.10.0; +6 more · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-33037
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-33037
Third Party Advisory
https://kc.mcafee.com/corporate/index?page=content&id=SB10366
lists.apache.org
https://lists.apache.org/thread.html/r290aee55b72811fd19e75ac80f6143716c079170c5671b96932ed44b%40%3Ccommits.tomee.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/r40f921575aee8d7d34e53182f862c45cbb8f3d898c9d4e865c2ec262%40%3Ccommits.tomee.apache.org%3E
Mailing List
https://lists.apache.org/thread.html/r612a79269b0d5e5780c62dfd34286a8037232fec0bc6f1a7e60c9381%40%3Cannounce.tomcat.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/rc6ef52453bb996a98cb45442871a1db56b7c349939e45d829bf9ae37%40%3Ccommits.tomee.apache.org%3E
lists.apache.org
https://lists.apache.org/thread.html/rd0dfea39829bc0606c936a16f6fca338127c86c0a1083970b45ac8d2%40%3Ccommits.tomee.apache.org%3E
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