CVE-2017-5647: A bug in the handling of the pipelined requests in Apache Tomcat 9.0.0.M1 to 9.0.0.M18, 8.5.0 to 8.5.12, 8.0.0

This week

HIGH 7.5REMOTEWATCHLISTDOWNGRADE

CVE-2017-5647 is a high-severity flaw (CVSS 7.5) affecting tomcat. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A bug in the handling of the pipelined requests in Apache Tomcat 9.0.0.M1 to 9.0.0.M18, 8.5.0 to 8.5.12, 8.0.0.RC1 to 8.0.42, 7.0.0 to 7.0.76, and 6.0.0 to 6.0.52, when send file was used, results in the pipelined request being lost when send file processing of the previous request completed. This could result in responses appearing to be sent for the wrong request. For example, a user agent that sent requests A, B and C could see the correct res

Why this priority

High severity
EPSS top 3%: very likely to be exploited
Remotely exploitable, no login, no user action
On your watchlist

No fix is published yet: follow the downgrade or mitigation steps.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	16.8% (top 3%)
CISA exploited list	No
Weakness	CWE-200
Published	2017-04-17
Last modified	2026-11-02

Publisher (CNA): Apache Software Foundation · Vendor: apache

Last updated 2026-11-02 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2017-04-17 16:59 UTCPublished CVE record published
2026-11-02 18:18 UTCUpdated Record last modified

apache tomcat DOWNGRADE

Affected: 6.0.0 · 6.0.1 · 6.0.2 · 6.0.3 · 6.0.4 · 6.0.5 · 6.0.6 · 6.0.7

Fixed in: no fixed release known

Safe to downgrade to: a release before 6.0.0

1. Check installed version

apt-cache policy tomcat || rpm -q tomcat || tomcat --version

2. No fixed release: DOWNGRADE to a release before 6.0.0 (Debian / Ubuntu)

apt-cache madison tomcat sudo apt install tomcat=<VERSION_BEFORE_6.0.0> sudo apt-mark hold tomcat

2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)

dnf --showduplicates list tomcat sudo dnf downgrade tomcat-<VERSION_BEFORE_6.0.0> sudo dnf versionlock add tomcat

Downgrade risk

Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.

After downgrade

Restart the service, and keep the package held until a fixed release ships.

Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.

Quick answers

How do I fix CVE-2017-5647?

tomcat: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2017-5647 being exploited?

CVE-2017-5647 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.

What does CVE-2017-5647 affect?

CVE-2017-5647 affects tomcat. Severity is high (CVSS 7.5). A bug in the handling of the pipelined requests in Apache Tomcat 9.0.0.M1 to 9.0.0.M18, 8.5.0 to 8.5.12, 8.0.0.RC1 to 8.0.42, 7.0.0 to 7.0.76, and 6.0.0 to 6.0.52, when send file was used, results in the pipelined request being lost when se

How urgent is CVE-2017-5647?

Priority 61/100. High severity; EPSS top 3%: very likely to be exploited; Remotely exploitable, no login, no user action; On your watchlist

Software pages

Apache Tomcat vulnerabilities

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References

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