The code in Apache Tomcat 9.0.0.M1 to 9.0.0.M11, 8.5.0 to 8.5.6, 8.0.0.RC1 to 8.0.38, 7.0.0 to 7.0.72, and 6.0.0 to 6.0.47 that parsed the HTTP request line permitted invalid characters. This could be exploited, in conjunction with a proxy that also permitted the invalid characters but with a different interpretation, to inject data into the HTTP response. By manipulating the HTTP response the attacker could poison a web-cache, perform an XSS attack and/or obtain sensitive information from requests other then their own.
CVE-2016-6816
This high-severity CVE scores 7.1 under NVD CVSS v3. EPSS exploit probability: 39.6%, top 2% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
A fix is available — apply it.
- CVSS v3
- 7.1
- EG Score
- 7.1(medium)
- EPSS
- 98.5%
- KEV
- Not listed
Published
March 20, 2017
Last Modified
May 13, 2026
References (72)
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0244.html
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0245.html
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0246.html
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0247.html
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0250.html
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0457.html
- security@apachehttp://rhn.redhat.com/errata/RHSA-2017-0527.html
- security@apachehttp://www.debian.org/security/2016/dsa-3738
- security@apachehttp://www.oracle.com/technetwork/security-advisory/cpuoct2017-3236626.html
- security@apachehttp://www.securityfocus.com/bid/94461
- security@apachehttp://www.securitytracker.com/id/1037332
- security@apachehttps://access.redhat.com/errata/RHSA-2017:0455
- security@apachehttps://access.redhat.com/errata/RHSA-2017:0456
- security@apachehttps://access.redhat.com/errata/RHSA-2017:0935
- security@apachehttps://lists.apache.org/thread.html/343558d982879bf88ec20dbf707f8c11255f8e219e81d45c4f8d0551%40%3Cdev.tomcat.apache.org%3E
Patch Availability(12)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| ubuntu | tomcat8 (8.0.37-1ubuntu0.1) @ yakkety | 2026-05-22 | ubuntu |
| ubuntu | libservlet2.5-java-doc (6.0.45+dfsg-1ubuntu0.1) @ xenial | 2026-05-22 | ubuntu |
| redhat | tomcat-0:7.0.69-11.el7_3 | 2017-04-12 | redhat |
| redhat | tomcat6-0:6.0.24-105.el6_8 | 2017-03-15 | redhat |
| redhat | patch | 2017-03-07 | redhat |
| redhat | tomcat-vault-0:1.0.8-9.Final_redhat_2.1.ep7.el6 | 2017-03-07 | redhat |
| redhat | tomcat-vault-0:1.0.8-9.Final_redhat_2.1.ep7.el7 | 2017-03-07 | redhat |
| redhat | resteasy-0:2.3.16-1.Final_redhat_1.1.ep6.el5 | 2017-02-02 | redhat |
| redhat | resteasy-0:2.3.16-1.Final_redhat_1.1.ep6.el6 | 2017-02-02 | redhat |
| redhat | resteasy-0:2.3.16-1.Final_redhat_1.1.ep6.el7 | 2017-02-02 | redhat |
| redhat | patch | 2017-02-02 | redhat |
| redhat | jboss-ec2-eap-0:7.5.13-1.Final_redhat_2.ep6.el6 | 2017-02-02 | redhat |
Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.
Affected Packages
(1 across 1 ecosystem)
Maven(1)
| Package | Vulnerable range | Fixed in | Dependents |
|---|---|---|---|
| org.apache.tomcat:tomcat-coyote | — | 6.0.48 | — |
All Vendor Advisories
(12)
Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.
- Red HatRHSA-2017:0244MODERATE2016-11-22
RHSA-2017:0244 — Moderate
- Red HatRHSA-2017:0245MODERATE2016-11-22
RHSA-2017:0245 — Moderate
- Red HatRHSA-2017:0246MODERATE2016-11-22
RHSA-2017:0246 — Moderate
- Red HatRHSA-2017:0247MODERATE2016-11-22
RHSA-2017:0247 — Moderate
- Red HatRHSA-2017:0250MODERATE2016-11-22
RHSA-2017:0250 — Moderate
- Red HatRHSA-2017:0455MODERATE2016-11-22
RHSA-2017:0455 — Moderate
- Red HatRHSA-2017:0456MODERATE2016-11-22
RHSA-2017:0456 — Moderate
- Red HatRHSA-2017:0457MODERATE2016-11-22
RHSA-2017:0457 — Moderate
- Red HatRHSA-2017:0527MODERATE2016-11-22
RHSA-2017:0527 — Moderate
- Red HatRHSA-2017:0935MODERATE2016-11-22
RHSA-2017:0935 — Moderate
- UbuntuUSN-3177-1MEDIUM
Tomcat vulnerabilities
- UbuntuUSN-4557-1MEDIUM
Tomcat vulnerabilities
Data Freshness Timeline
(refreshed 11× in last 7d / 33× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.
- 2026-07-22 22:03 UTCEG score recompute
- 2026-07-22 14:04 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-21 15:21 UTCEPSS rescore
- 2026-07-20 17:04 UTCEPSS rescore
- 2026-07-19 02:26 UTCEPSS rescore
- 2026-07-19 02:26 UTCEPSS rescore
- 2026-07-18 10:00 UTCEPSS rescore
- 2026-07-18 10:00 UTCEPSS rescore
- 2026-07-16 16:59 UTCEPSS rescore
- 2026-07-16 16:59 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 16:54 UTCEPSS rescore
- 2026-07-15 01:56 UTCEPSS rescore
- 2026-07-13 22:26 UTCEPSS rescore
- 2026-07-13 06:09 UTCEPSS rescore
- 2026-07-12 05:43 UTCEPSS rescore
- 2026-07-12 05:43 UTCEPSS rescore
- 2026-07-12 01:52 UTCOSV refresh
- 2026-07-11 08:24 UTCEPSS rescore
- 2026-07-09 19:06 UTCEPSS rescore
- 2026-07-08 15:10 UTCEPSS rescore
- 2026-07-04 06:28 UTCEPSS rescore
- 2026-07-01 15:02 UTCEPSS rescore
- 2026-06-30 23:19 UTCEPSS rescore
Show 57 moreShow fewer
- 2026-06-30 23:19 UTCEPSS rescore
- 2026-06-29 14:03 UTCEPSS rescore
- 2026-06-28 04:53 UTCEPSS rescore
- 2026-06-27 03:05 UTCEPSS rescore
- 2026-06-25 13:47 UTCEPSS rescore
- 2026-06-24 14:02 UTCEPSS rescore
- 2026-06-23 21:30 UTCEPSS rescore
- 2026-06-23 08:30 UTCOSV refresh
- 2026-06-22 14:23 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-21 01:57 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-18 17:50 UTCEPSS rescore
- 2026-06-17 17:50 UTCEPSS rescore
- 2026-06-17 17:50 UTCEPSS rescore
- 2026-06-16 17:50 UTCEPSS rescore
- 2026-06-15 17:45 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-14 23:14 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-13 22:57 UTCEPSS rescore
- 2026-06-12 23:09 UTCEPSS rescore
- 2026-06-11 13:57 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-07 15:22 UTCEPSS rescore
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-06 13:45 UTCEPSS rescore
- 2026-06-06 07:34 UTCOSV refresh
- 2026-06-05 22:44 UTCEPSS rescore
- 2026-06-04 13:10 UTCEPSS rescore
- 2026-06-04 13:10 UTCEPSS rescore
- 2026-06-02 20:10 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-06-01 13:49 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 22:28 UTCEPSS rescore
- 2026-05-31 00:14 UTCEPSS rescore
- 2026-05-29 13:41 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-28 13:42 UTCEPSS rescore
- 2026-05-27 13:38 UTCEPSS rescore
- 2026-05-27 13:38 UTCEPSS rescore
- 2026-05-26 13:42 UTCEPSS rescore
- 2026-05-26 13:42 UTCEPSS rescore
- 2026-05-26 07:17 UTCEPSS rescore
- 2026-05-24 16:44 UTCEPSS rescore
- 2026-05-22 21:15 UTCEPSS rescore
- 2026-05-22 15:10 UTCEG score recompute
- 2026-05-22 15:10 UTCVendor advisory
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 22:37 UTCEPSS rescore
- 2026-05-20 11:21 UTCEPSS rescore
- 2026-05-20 11:21 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
- 2026-05-18 21:30 UTCEPSS rescore
Publicly available exploits
(1 reference)Working exploit code is in the public domain (1 Exploit-DB entry). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.
- Exploit-DBEDB-41783First seen Apr 4, 2017
Apache Tomcat 6/7/8/9 - Information Disclosure
Open source ↗
Frequently asked(5)
What is CVE-2016-6816?
When was CVE-2016-6816 disclosed?
Is CVE-2016-6816 actively exploited?
What is the CVSS score of CVE-2016-6816?
How do I remediate CVE-2016-6816?
Dependency Blast Radius
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