CVE-2026-43515
A public proof of concept exists; no exploitation attested.
- Published2026-05-12
- Fixed in11.0.22 · 10.1.55 · 9.0.118
- WeaknessCWE-285
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
Improper Authorization vulnerability when multiple method constraints define an HTTP method for the same extension in Apache Tomcat. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.21, from 10.1.0-M1 through 10.1.54, from 9.0.0.M1 through 9.0.117, from 8.5.0 through 8.5.100, from 7.0.0 through 7.0.109. Users are recommended to upgrade to version 11.0.22, 10.1.55 or 9.0.118 which fix the issue.
Timeline
dates in UTC- 2026-05-1216:16CVE publishedNVD
- 2026-10-2319:23First public proof of conceptPoC-in-GitHub
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2026-43515?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2026-43515?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD · OSV| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 11.0 | ≥ 11.0.0, < 11.0.22 | 11.0.22 | NVD · OSV |
| 11.0 | ≥ 11.0.0-M1, < 11.0.22 | 11.0.22 | OSV |
| 10.1 | ≥ 10.1.0, < 10.1.55 | 10.1.55 | NVD |
| 10.1 | ≥ 10.1.0-M1, < 10.1.55 | 10.1.55 | OSV |
| 10.x | ≥ 10.0.0, < 10.1.55 | 10.1.55 | OSV |
| 9.0 | ≥ 9.0.0, < 9.0.118 | 9.0.118 | NVD · OSV |
| 9.0 | < 9.0.118 | 9.0.118 | OSV |
| 7.0 | ≥ 7.0.0, ≤ 7.0.109 | no fix published | NVD |
| 8.5 | ≥ 8.5.0, ≤ 8.5.100 | no fix published | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Distribution builds and vendor advisories
Packages from OSV.dev and products from the vendors' CSAF advisories.
version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.
Packages
- tomcatAlmaLinux:10all versions · fixed in 1:10.1.49-4.el10_2.alma.1and 7 other packages
- tomcatAlmaLinux:9all versions · fixed in 1:9.0.120-2.el9_8and 7 other packages
- tomcatAlmaLinux:8all versions · fixed in 1:9.0.120-1.el8_10and 7 other packages
- tomcat9AlmaLinux:10all versions · fixed in 1:9.0.120-1.el10_2.alma.1and 7 other packages
Vendor advisories
Red Hat Security Advisory: tomcat update
Red Hat Security Advisory: tomcat9 security update
Red Hat Security Advisory: tomcat security update
Red Hat Security Advisory: tomcat security, bug fix, and enhancement update
Red Hat Security Advisory: tomcat security update
Red Hat Security Advisory: tomcat security update
10 more advisories
Fix
- Update Apache Tomcat to 11.0.22 · 10.1.55 · 9.0.118
- Vendor fix Red Hat Product Security RHSA-2026:69259 · 9 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258
- Vendor fix Red Hat Product Security RHSA-2026:43401 · 33 productsBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
- Vendor fix Red Hat Product Security RHSA-2026:43402 · 1 productBefore applying the update, back up your existing Red Hat JBoss Web Server installation, including all applications and configuration files. The References section of this erratum contains a download link for the update. You must be logged in to download the update.
- Vendor fix Red Hat Product Security RHSA-2026:16528 · 21 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://images.redhat.com/
- Workaround from the vendor Red Hat Product Security RHSA-2026:69259 · 9 productsMitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.
Advisories and patches
- lists.apache.orgVendor Advisory
Detection
read 2026-10-23 19:25 UTC- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
Sources
- NVDCVE recordread 2026-10-23
- CISA-ADPSSVC decisionnone2026-05-14
- OpenCVESSVC decisionnone—
- CISA-ADPCVSS 3.19.12026-05-14
- CNAweakness (CWE)CWE-285read 2026-10-23
- FIRST EPSSEPSS score1.2 %2026-10-22
- PoC-in-GitHubproof of concept1read 2026-10-23
- OSVaffected packages—
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
- Published
- 2026-05-12
- Last Modified
- 2026-06-17
- NVD status
- Analyzed
Frequently asked questions
What is CVE-2026-43515?
Is CVE-2026-43515 actively exploited?
What is the CVSS score for CVE-2026-43515?
Running Apache Tomcat? Hear about its next vulnerability
Surveillance reads the versions in your stack — a domain, a lockfile or a list — checks each CVE against the ranges its sources publish, and alerts you when one you run is exploited or enters CISA KEV. A version it cannot read stays « version not verified ».
No credit card required · No monthly cap on website lookups · 250 API requests/month
Go further
- Following what attackers exploit right now? The CISA KEV additions of the month, with their patch deadlines.
- Running this software? Vulnerability monitoring alerts you to new vulnerabilities in your products.
Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.