CVE-2026-78383
published 2026-09-23CVE-2026-78383: Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread…
PriorityP346high7.5CVSS 3.1
AVNACLPRNUINSUCNINAH
EPSS
0.38%
30.4th percentile
Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
Affected
8 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| apache | tomcat | — | — |
| apache_software_foundation | apache_tomcat | 10.1.0-M1 – 10.1.59 | — |
| apache_software_foundation | apache_tomcat | 11.0.0-M1 – 11.0.25 | — |
| apache_software_foundation | apache_tomcat | 7.0.0 – 7.0.109 | — |
| apache_software_foundation | apache_tomcat | 8.5.0 – 8.5.100 | — |
| apache_software_foundation | apache_tomcat | 9.0.0.M1 – 9.0.121 | — |
| debian | tomcat9 | — | — |
| pki-deps_10.6 | pki-servlet-engine | — | — |
CVSS provenance
nvdv3.17.5HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
vendor_redhat7.5HIGH
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Red Hat
tomcat: Apache Tomcat: Denial of Service via AJP request
vendor_redhat·2026-09-23·CVSS 7.5
CVE-2026-78383 [HIGH] CWE-770 tomcat: Apache Tomcat: Denial of Service via AJP request
tomcat: Apache Tomcat: Denial of Service via AJP request
Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
A flaw was found in Apache Tomcat. An unauthenticated remote attacker can send a specially crafted AJP (Apache JServ Protocol) request,
GHSA
Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.
ghsa_unreviewed·2026-09-23
CVE-2026-78383 CWE-770 Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.
Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
No detection rules found.
No public exploits indexed.
Hackernews
⚡ Weekly Recap: NetScaler and FortiMail 0-Days, AI Coding Leaks, Spectre v2 and Ransomware Arrests
blogs_hackernews·2026-10-05·CVSS 7.5
CVE-2026-88779 [HIGH] ⚡ Weekly Recap: NetScaler and FortiMail 0-Days, AI Coding Leaks, Spectre v2 and Ransomware Arrests
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## ⚡ Weekly Recap: NetScaler and FortiMail 0-Days, AI Coding Leaks, Spectre v2 and Ransomware Arrests
A blank field. A public repo. One reply to an email. A box left exposed. None of this sounds dramatic, which is partly the problem. This week’s threats keep finding leverage in small things that were easy to overlook.
There are actively exploited bugs in the mix, cleaner intrusion paths, smarter automation, and a long patch list waiting behind them. Some attacks are getting more capable. Others are still getting in because the basics gave way first.
Here’s what mattered this week.
## ⚡ Threat of the Week
Citrix Warns of Ne
Bugzilla
CVE-2026-73581 CVE-2026-75973 CVE-2026-76183 CVE-2026-77756 CVE-2026-77762 CVE-2026-77791 CVE-2026-78383 CVE-2026-78437 CVE-2026-79677 CVE-2026-86248 CVE-2026-86350 CVE-2026-87022 tomcat: various flaw
bugzilla·2026-09-29·CVSS 9.8
CVE-2026-73581 [CRITICAL] CVE-2026-73581 CVE-2026-75973 CVE-2026-76183 CVE-2026-77756 CVE-2026-77762 CVE-2026-77791 CVE-2026-78383 CVE-2026-78437 CVE-2026-79677 CVE-2026-86248 CVE-2026-86350 CVE-2026-87022 tomcat: various flaw
CVE-2026-73581 CVE-2026-75973 CVE-2026-76183 CVE-2026-77756 CVE-2026-77762 CVE-2026-77791 CVE-2026-78383 CVE-2026-78437 CVE-2026-79677 CVE-2026-86248 CVE-2026-86350 CVE-2026-87022 tomcat: various flaws [fedora-all]
Disclaimer: Community trackers are created by Red Hat Product Security team on a best effort basis. Package maintainers are required to ascertain if the flaw indeed affects their package, before starting the update process.
Improper handling of length parameter inconsistency vulnerability in Apache Tomcat allows WebSocket message smuggling when per-message-deflate is used.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121.
The following versions were EOS at the time the CVE was created but are kn
Bugzilla
CVE-2026-78383 tomcat: Apache Tomcat: Denial of Service via AJP request
bugzilla·2026-09-23·CVSS 7.5
CVE-2026-78383 [HIGH] CVE-2026-78383 tomcat: Apache Tomcat: Denial of Service via AJP request
CVE-2026-78383 tomcat: Apache Tomcat: Denial of Service via AJP request
Allocation of resources without limits or throttling vulnerability in Apache Tomcat allows an unauthenticated AJP request to pin an AJP processing thread leading to denial of service.
This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121.
The following versions were EOL at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Other unsupported versions may also be affected.
Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.0.122, which fix the issue.
2026-09-23
Published