CVE-2021-30639
A vulnerability in Apache Tomcat allows an attacker to remotely trigger a denial of service.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (6.89%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
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.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 6.89% probability · 94th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-755
- Affected
- apache/tomcat · mcafee/epolicy orchestrator · oracle/big data spatial and graph
- Source
- security@apache.org
References
- https://kc.mcafee.com/corporate/index?page=content&id=SB10366Third Party Advisory
- https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cusers.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/rd84fae1f474597bdf358f5bdc0a5c453c507bd527b83e8be6b5ea3f4%40%3Cannounce.tomcat.apache.org%3EMailing List, Vendor Advisory
- https://security.gentoo.org/glsa/202208-34Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210827-0007/Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
- https://kc.mcafee.com/corporate/index?page=content&id=SB10366Third Party Advisory
- https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cdev.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/r79a7c019712b39aedf7cf4da9276d80610f04441b2a4f6506cb2daaf%40%3Cusers.tomcat.apache.org%3E
- https://lists.apache.org/thread.html/rd84fae1f474597bdf358f5bdc0a5c453c507bd527b83e8be6b5ea3f4%40%3Cannounce.tomcat.apache.org%3EMailing List, Vendor Advisory
- https://security.gentoo.org/glsa/202208-34Third Party Advisory
- https://security.netapp.com/advisory/ntap-20210827-0007/Third Party Advisory
- https://www.oracle.com/security-alerts/cpujan2022.htmlPatch, Third Party Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.