Potential HTTP request smuggling in Apache Tomcat

Description

The refactoring present in Apache Tomcat versions 9.0.28 to 9.0.30, 8.5.48 to 8.5.50 and 7.0.98 to 7.0.99 introduced a regression. The result of the regression was that invalid Transfer-Encoding headers were incorrectly processed leading to a possibility of HTTP Request Smuggling if Tomcat was located behind a reverse proxy that incorrectly handled the invalid Transfer-Encoding header in a particular manner. Such a reverse proxy is considered unlikely.

Basic information

Type
reviewed
Severity
medium
Advisory on GitHub
Open advisory ↗
Repository advisory
Source code
Not specified
Published (advisory)
2020-02-28 01:10:58 UTC
Updated
2023-01-29 05:01:46 UTC
GitHub reviewed
2020-02-25 16:19:11 UTC
NVD published
2020-02-24

EPSS Score

Score Percentile
6.16% 90.78%

CVSS Scores

Base score Version Severity Vector
4.8 3.1
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.

Identifiers

CWEs

CWE id Name
CWE-444 Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Affected packages (6)

Vulnerable version ranges and first patched releases as published by GitHub.

Ecosystem Package Vulnerable range First patched Vulnerable functions
maven org.apache.tomcat.embed:tomcat-embed-core >= 7.0.98, < 7.0.100 7.0.100
maven org.apache.tomcat.embed:tomcat-embed-core >= 8.5.48, < 8.5.51 8.5.51
maven org.apache.tomcat.embed:tomcat-embed-core >= 9.0.28, < 9.0.31 9.0.31
maven org.apache.tomcat:tomcat >= 7.0.98, < 7.0.100 7.0.100
maven org.apache.tomcat:tomcat >= 8.5.48, < 8.5.51 8.5.51
maven org.apache.tomcat:tomcat >= 9.0.28, < 9.0.31 9.0.31

References

cvelogic Threat Intelligence