CVE-2019-19337

A flaw was found in the way the Ceph RADOS Gateway daemon handles S3 requests. An authenticated attacker can abuse this flaw by causing a remote denial of service by sending a specially crafted HTTP Content-Length header to the Ceph RADOS Gateway server.

This flaw only affects Red Hat Ceph Storage 3, upstream versions of ceph are not affected.

The ceph package distributed by Red Hat Enterprise Linux 7 and 8 are not affected by this issue, as it doesn't ship any server-side library.

Red Hat OpenStack now consumes fixes directly from the base ceph channels . Therefore the ceph package provided by Red Hat OpenStack 13 has been marked as 'will not fix'.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

1. By default system will use /etc/init.d/ceph-radosgw, stop this service by ~]# /etc/init.d/ceph-radosgw stop

2. Create systemd service, and change command line parameters according to the environment where Ceph radosgw is running.

~]# cat /usr/lib/systemd/system/ceph-rgw.service [Unit] Description=Ceph RGW daemon

[Service] Type=forking ExecStart=/bin/radosgw -n client.rgw.$(HOSTNAME REDACTED) Restart=on-abnormal RestartSec=1s

[Install] WantedBy=multi-user.target

3. Run systemd service 'ceph-rgw.service'

Caveat: It still takes +1-2 sec to get service back online. After applying above mentioned mitigation, the malicious IP can be blocked by a firewall rule if there are continuous attempts to launch remote denial of service. This mitigation is of limited use if the attack is launched from multiple IPs. It is recommended to limit the exposure of ceph RGW server to known clients.