CVE-2017-5651
Expected Behavior Violation in Apache Tomcat
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
NVD Score used
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
- Record
CVE-2017-5651- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Updated
- 2026-11-02
CVE List No score
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
- Record
CVE-2017-5651- Updated
- 2026-11-02
EUVDEUVD-2022-3384 No score
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
- Record
EUVD-2022-3384- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-9hg2-395j-83rm
Expected Behavior Violation in Apache Tomcat
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
- Record
GHSA-9hg2-395j-83rm- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-440
- Updated
- 2026-11-02
OSV
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
- Record
CVE-2017-5651- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVGHSA-9hg2-395j-83rm
Expected Behavior Violation in Apache Tomcat
In Apache Tomcat 9.0.0.M1 to 9.0.0.M18 and 8.5.0 to 8.5.12, the refactoring of the HTTP connectors introduced a regression in the send file processing. If the send file processing completed quickly, it was possible for the Processor to be added to the processor cache twice. This could result in the same Processor being used for multiple requests which in turn could lead to unexpected errors and/or response mix-up.
- Record
GHSA-9hg2-395j-83rm- CVSS 3.0
- 9.8 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-440
- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
org.apache.tomcat:tomcat-coyoteMaven |
9.0.0.M1 to 9.0.0.M18 | 9.0.0.M19 |
org.apache.tomcat:tomcat-coyoteMaven |
8.5.0 to 8.5.12 | 8.5.13 |
org.apache.tomcat.embed:tomcat-embed-coreMaven |
9.0.0.M1 to 9.0.0.M18 | 9.0.0.M19 |
org.apache.tomcat.embed:tomcat-embed-coreMaven |
8.5.0 to 8.5.12 | 8.5.13 |
org.apache.tomcat:tomcat-coyoteMaven |
9.0.0.M1 up to 9.0.0.M19, plus listed versions 9.0.0.M109.0.0.M119.0.0.M139.0.0.M159.0.0.M17 Show 6 moreShow less9.0.0.M189.0.0.M39.0.0.M49.0.0.M69.0.0.M89.0.0.M9 |
9.0.0.M19 |
org.apache.tomcat:tomcat-coyoteMaven |
8.5.0 up to 8.5.13, plus listed versions 8.5.118.5.128.5.28.5.38.5.4 Show 4 moreShow less8.5.58.5.68.5.88.5.9 |
8.5.13 |
org.apache.tomcat.embed:tomcat-embed-coreMaven |
9.0.0.M1 up to 9.0.0.M19, plus listed versions 9.0.0.M109.0.0.M119.0.0.M139.0.0.M159.0.0.M17 Show 6 moreShow less9.0.0.M189.0.0.M39.0.0.M49.0.0.M69.0.0.M89.0.0.M9 |
9.0.0.M19 |
org.apache.tomcat.embed:tomcat-embed-coreMaven |
8.5.0 up to 8.5.13, plus listed versions 8.5.118.5.128.5.28.5.38.5.4 Show 4 moreShow less8.5.58.5.68.5.88.5.9 |
8.5.13 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2017-5651 is a critical vulnerability (CVSS 9.8) in Apache Tomcat, published April 17, 2017. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 7.75%, the 94th percentile. Fixed in org.apache.tomcat:tomcat-coyote 9.0.0.M19.
References
securityfocus.com/bid/97544
security.gentoo.org/glsa/201705-09
security.netapp.com/advisory/ntap-20180614-0001
lists.apache.org/thread.html/6694538826b87522fb723d2dcedd537e14ebe0a381d92e5525a531d8%40%3Cannounce.tomcat.apache.org%3E
securitytracker.com/id/1038219
oracle.com/technetwork/security-advisory/cpujul2017-3236622.html
Show 26 moreShow less
bz.apache.org/bugzilla/show_bug.cgi?id=60918
nvd.nist.gov/vuln/detail/CVE-2017-5651
web.archive.org/web/20170417124228/http://www.securityfocus.com/bid/97544
github.com/apache/tomcat/commit/494429ca210641b6b7affe89a2b0a6c0ff70109b