Bug 1981540 (CVE-2021-30639)

Summary: CVE-2021-30639 tomcat: non-blocking I/O error flag is not reset between requests
Product: [Other] Security Response Reporter: Guilherme de Almeida Suckevicz <gsuckevi>
Component: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED WONTFIX QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: aileenc, akoufoud, alazarot, alee, almorale, anstephe, asoldano, atangrin, avibelli, bbaranow, bgeorges, bmaxwell, brian.stansberry, cdewolf, chazlett, cmoulliard, coolsvap, csutherl, darran.lofthouse, dbecker, dkreling, dosoudil, drieden, eleandro, etirelli, fjuma, ggaughan, gmalinko, gzaronik, huwang, ibek, ikanello, ivan.afonichev, iweiss, janstey, java-sig-commits, jclere, jjoyce, jochrist, jolee, jpallich, jperkins, jrokos, jschatte, jschluet, jstastny, jwon, krathod, krzysztof.daniel, kverlaen, kwills, lgao, lhh, lpeer, lthon, mburns, mkolesni, mnovotny, msochure, msvehla, mszynkie, nwallace, peholase, pgallagh, pjindal, pmackay, rguimara, rhcs-maint, rrajasek, rruss, rstancel, rsvoboda, sclewis, scohen, slinaber, smaestri, szappis, tom.jenkinson, tzimanyi, yborgess, yozone
Target Milestone: ---Keywords: Security
Target Release: ---   
Hardware: All   
OS: Linux   
Whiteboard:
Fixed In Version: tomcat 10.0.5, tomcat 9.0.45, tomcat 8.5.65 Doc Type: If docs needed, set a value
Doc Text:
A flaw was found in Apache Tomcat. This flaw 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 means that once a non-blocking I/O error occurred, all future requests handled by that request object would fail. Users can trigger non-blocking I/O errors (ex. by dropping a connection), creating the possibility of triggering a denial of service. Applications that do not use non-blocking I/O are not exposed to this vulnerability. The highest threat from this vulnerability is to system availability.
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Clone Of: Environment:
Last Closed: 2021-07-29 07:06:49 UTC Type: ---
Regression: --- Mount Type: ---
Documentation: --- CRM:
Verified Versions: Category: ---
oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
Embargoed:
Bug Depends On: 1981541    
Bug Blocks: 1981546    

Description Guilherme de Almeida Suckevicz 2021-07-12 18:59:53 UTC 
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.

Reference:
https://lists.apache.org/thread.html/rd84fae1f474597bdf358f5bdc0a5c453c507bd527b83e8be6b5ea3f4%40%3Cannounce.tomcat.apache.org%3E
Comment 1 Guilherme de Almeida Suckevicz 2021-07-12 19:00:22 UTC 
Created tomcat tracking bugs for this issue:

Affects: fedora-all [bug 1981541]
Comment 5 Product Security DevOps Team 2021-07-29 07:06:49 UTC 
This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2021-30639