CVE-2023-46589 | Apache Tomcat: HTTP request smuggling via malformed trailer headers

Improper Input Validation vulnerability in Apache Tomcat.Tomcat from 11.0.0-M1 through 11.0.0-M10, from 10.1.0-M1 through 10.1.15, from 9.0.0-M1 through 9.0.82 and from 8.5.0 through 8.5.95 did not correctly parse HTTP trailer headers. A trailer header that exceeded the header size limit could cause Tomcat to treat a single request as multiple requests leading to the possibility of request smuggling when behind a reverse proxy. Older, EOL versions may also be affected. Users are recommended to upgrade to version 11.0.0-M11 onwards, 10.1.16 onwards, 9.0.83 onwards or 8.5.96 onwards, which fix the issue.

Published: 2023-11-28 Last update: 2025-08-07 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2023-46589 is rated Moderate Risk (63.7/100): CVSS High severity, with high exploitation likelihood (EPSS 53.16%, 98th percentile). Core evidence: EPSS ranks this CVE among the most likely to be exploited in the near term. Mandatory action: High exploitation likelihood—assess exposure and prioritize remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2023-46589

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-05 53.73% 53.16% -0.57%
2 2026-05-23 53.16% 53.73% +0.57%
3 2026-05-20 53.16%

Full EPSS history (55 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-46589

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 [email protected]
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 3.6 134c704f-9b21-4f2e-91b3-4a467353bcc0

Weakness enumeration for CVE-2023-46589

GitHub Security Advisory for CVE-2023-46589

GHSA-fccv-jmmp-qg76 · Severity: high · Ecosystem: maven — Apache Tomcat Improper Input Validation vulnerability

OS Trackers for CVE-2023-46589

vendor priority summary link
debian not yet assigned CVE-2023-46589 not yet assigned priority: Debian including 2 source packages (tomcat10, tomcat9), 9 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 9. https://security-tracker.debian.org/tracker/CVE-2023-46589
redhat high https://access.redhat.com/security/cve/CVE-2023-46589
suse medium https://www.suse.com/security/cve/CVE-2023-46589/
ubuntu medium CVE-2023-46589 medium priority: Ubuntu including 6 source packages (tomcat10, tomcat11, tomcat6, tomcat7, tomcat8, tomcat9), 60 status rows across 12 suites (bionic, focal, jammy, lunar, mantic, noble, oracular, plucky, questing, trusty, upstream, xenial): DNE 25, ignored 18, released 10, not-affected 5, needs-triage 2. https://ubuntu.com/security/CVE-2023-46589

Affected software / configurations for CVE-2023-46589

Vendor Product Version Raw CPE
apache tomcat >= 8.5.0, < 8.5.96 cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*
apache tomcat >= 9.0.0, < 9.0.83 cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*
apache tomcat >= 10.1.0, < 10.1.16 cpe:2.3:a:apache:tomcat:*:*:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone1:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone10:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone2:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone3:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone4:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone5:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone6:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone7:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone8:*:*:*:*:*:*
apache tomcat 11.0.0 cpe:2.3:a:apache:tomcat:11.0.0:milestone9:*:*:*:*:*:*

References for CVE-2023-46589

cvelogic Threat Intelligence