CVE-2021-30639Not scoredCWE-755

CVE-2021-30639: DoS after non-blocking IO error

Apache Software Foundation · Apache Tomcat

Vendor fix available · Affected: Apache Software Foundation Apache Tomcat · Exploitation: possible (1 to 10%)

Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.

6.9%probability of exploitation in the next 30 days

94th percentile

050100

Higher than 94% of scored CVEs

Not scored yet. The CVE record carries no CVSS score.

DescriptionCVE.org

A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service. An error introduced as part of a change to improve error handling during non-blocking I/O meant that the error flag associated with the Request object was not reset between requests. This meant that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users were able to trigger non-blocking I/O errors, e.g. by dropping a connection, thereby creating the possibility of triggering a DoS. Applications that do not use non-blocking I/O are not exposed to this vulnerability. This issue affects Apache Tomcat 10.0.3 to 10.0.4; 9.0.44; 8.5.64.

Affected products1

From the CVE record. A product or version that is not listed is unknown, not unaffected.

Apache Software Foundation · Apache TomcatApache Tomcat 10 10.0.3 to 10.0.4; Apache Tomcat 9 9.0.44; Apache Tomcat 8.5 8.5.64

On the Atlas

Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.

Open the Atlas

Exploitation: Possible (1 to 10%). EPSS between 1% and 10%.
CISA KEV: Not listed
Public check: No public nuclei template
Weakness: Improper Handling of Exceptional Conditions · Input Validation and Logic
Vendor: Apache Software Foundation
Published: July 2021
Band: Possible (1 to 10%), July 2021

CoverageNo articles yet

No CyberSIXT article names CVE-2021-30639 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.