cbcvebase.
CVE-2023-28709
published 2023-05-22

CVE-2023-28709: The fix for CVE-2023-24998 was incomplete for Apache Tomcat 11.0.0-M2 to 11.0.0-M4, 10.1.5 to 10.1.7, 9.0.71 to 9.0.73 and 8.5.85 to 8.5.87. If non-default…

PriorityP357high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
51.55%
98.8th percentile
The fix for CVE-2023-24998 was incomplete for Apache Tomcat 11.0.0-M2 to 11.0.0-M4, 10.1.5 to 10.1.7, 9.0.71 to 9.0.73 and 8.5.85 to 8.5.87. If non-default HTTP connector settings were used such that the maxParameterCount could be reached using query string parameters and a request was submitted that supplied exactly maxParameterCount parameters in the query string, the limit for uploaded request parts could be bypassed with the potential for a denial of service to occur.

Affected

7 ranges
VendorProductVersion rangeFixed in
apachetomcat
apachetomcat10.1.5 – 10.1.7
apachetomcat8.5.85 – 8.5.87
apachetomcat9.0.71 – 9.0.73
debiandebian_linux
debiantomcat10< tomcat10 10.1.6-1+deb12u1 (bookworm)tomcat10 10.1.6-1+deb12u1 (bookworm)
debiantomcat9< tomcat10 10.1.6-1+deb12u1 (bookworm)tomcat10 10.1.6-1+deb12u1 (bookworm)

Detection & IOCsextracted from sources · hover to see the quote

  • Exploit targets Apache Tomcat multipart/form-data upload endpoint when maxParameterCount is exhausted via query string parameters — monitor for requests that supply exactly maxParameterCount query string parameters combined with a multipart upload body, which may indicate an attempt to bypass the upload-parts limit and trigger DoS.
  • Exploitation requires non-default HTTP connector configuration (maxParameterCount tuned down or otherwise reachable via query string alone); instances using default Tomcat connector settings are not exploitable — focus detection on non-default deployments.
  • Attack vector is remote over HTTP; no authentication is required — prioritize monitoring of public-facing Tomcat HTTP connectors on affected versions (8.5.85–8.5.87, 9.0.71–9.0.73, 10.1.5–10.1.7, 11.0.0-M2–11.0.0-M4) for anomalous multipart upload traffic.
  • ·Vulnerability is only exploitable when non-default HTTP connector settings allow maxParameterCount to be reached purely via query string parameters; default Tomcat configurations are not affected.
  • ·Red Hat states no mitigation meeting their usability/stability standards is currently available; patching to a fixed version is the only remediation path.
  • ·pki-servlet-engine has been obsoleted in RHEL 8.9 and later by Tomcat; no additional fixes for the engine will be made available on that platform.

CVSS provenance

nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
ghsa7.5HIGH
osv7.5HIGH
vendor_debian7.5HIGH
vendor_oracle7.5HIGH
vendor_redhat7.5HIGH
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