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Full vulnerability report · 2026
CVE-2026-24880High confidence

Apache Tomcat: Request smuggling via invalid chunk extension

Apache Software Foundation · Apache Tomcat

7.5HighCVSS 3.1
Recommended action
Within 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
Distribution package intelligence

Ubuntu vendor package status

Canonical’s release and source-package findings are shown separately from local repository availability.

2 package states
Repository candidate not checked

A published vendor fix does not prove that a matching update is enabled and installable on a particular asset. Confirm the local package candidate before scheduling remediation.

Ubuntu releaseSource packageVendor stateFixed versionEvidence
Ubuntu 24.04 LTSnoble · esm-appstomcat10Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Ubuntu 24.04 LTSnoble · esm-appstomcat9Under evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical record ↗Source updated 10 Sept 2026
Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Select the national-authority views to include. The exact source language is shown on each matched advisory. Your choice is remembered on this device and encoded in the shareable URL.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-21006

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 7 days

High technical severity; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
01

What, why and how

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat via invalid chunk extension. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.1.0-M1 through 10.1.52, from 9.0.0.M1 through 9.0.115, 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 11.0.20, 10.1.52 or 9.0.116, which fix the issue.

What

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat via invalid chunk extension. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.1.0-M1 through 10.1.52, from 9.0.0.M1 through 9.0.115, 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 11.0.20, 10.1.52 or 9.0.116, which fix the issue.

Why

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') vulnerability in Apache Tomcat via invalid chunk extension. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.18, from 10.1.0-M1 through 10.1.52, from 9.0.0.M1 through 9.0.115, 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 11.0.20, 10.1.52 or 9.0.116, which fix the issue.

Why

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

How

An attacker operating through a network path may attempt exploitation without authentication or user interaction. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Unchanged: impact remains within the vulnerable component's security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-444

CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling'). The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

Common Vulnerability Scoring System 3.1: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SUnchangedScope: The security impact remains within the vulnerable component's authority.CNoneConfidentiality impact: No direct loss is represented by this metric.IHighIntegrity impact: A successful attack can cause a major loss.ANoneAvailability impact: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-444
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

BSI · German · WID-SEC-W-2026-1608Atlassian Produkte (Bamboo, Bitbucket, Confluence, Crucible, Fisheye und Jira): Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Atlassian Bitbucket, Atlassian Confluence, Atlassian Crucible, Atlassian Fisheye und Atlassian Jira ausnutzen, um beliebigen Programmcode auszuführen, um einen Denial of Service Angriff durchzuführen, um Informationen offenzulegen, um einen Cross-Site Scripting Angriff durchzuführen, und um Sicherheitsvorkehrungen zu umgehen.

Official advisory
BSI · German · WID-SEC-W-2026-1229Atlassian Bamboo, Bitbucket, Confluence, Jira: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Atlassian Bamboo, Atlassian Bitbucket, Atlassian Confluence und Atlassian Jira ausnutzen, um beliebigen Programmcode auszuführen, Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren oder offenzulegen oder Cross-Site-Scripting-Angriffe durchzuführen.

Official advisory
BSI · German · WID-SEC-W-2026-1038Apache Tomcat und Tomcat Native: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in Apache Tomcat ausnutzen, um Sicherheitsmaßnahmen zu umgehen, Daten zu manipulieren, vertrauliche Informationen offenzulegen, Open-Redirect-Angriffe durchzuführen und andere, nicht näher spezifizierte Angriffe auszuführen.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0958Multiples vulnérabilités dans les produits IBM

g/CVERecord?id=CVE-2026-22796 Référence CVE CVE-2026-2303 https://www.cve.org/CVERecord?id=CVE-2026-2303 Référence CVE CVE-2026-2332 https://www.cve.org/CVERecord?id=CVE-2026-2332 Référence CVE CVE-2026-2359 https://www.cve.org/CVERecord?id=CVE-2026-2359 Référence CVE CVE-2026-23745 https://www.cve.org/CVERecord?id=CVE-2026-23745 Référence CVE CVE-2026-2391 https://www.cve.org/CVERecord?id=CVE-2026-2391 Référence CVE CVE-2026-23950 https://www.cve.org/CVERecord?id=CVE-2026-23950 Référence CVE CVE-2026-2482 https://www.cve.org/CVERecord?id=CVE-2026-2482 Référence CVE CVE-2026-24842 https://www.cve.org/CVERecord?id=CVE-2026-24842 Référence CVE CVE-2026-24880 https://www.cve.org/CVERecord?id=CVE-2026-24880 Référence CVE CVE-2026-25639 https://www.cve.org/CVERecord?id=CVE-2026-25639 Référence CVE CVE-2026-25680 https://www.cve.org/CVERecord?id=CVE-2026-25680 Référence CVE CVE-2026-25681 https://www.cve.org/CVERecord?id=CVE-2026-25681 Référence CVE CVE-2026-25854 https://www.cve.org/CVERecord?id=CVE-2026-25854 Référence CVE CVE-2026-26960 https://www.cve.org/CVERecord?id=CVE-2026-26960 Référence CVE CVE-2026-26996 https://www.cve.org/CVERecord?id=CVE-2026-26996 Référence CVE CVE-2026-27136 https://www.cve.org/CVERecord?id=CVE-2026-27136 Référence CVE CVE-2026-27727 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0933Multiples vulnérabilités dans les produits IBM

ERecord?id=CVE-2026-15057 Référence CVE CVE-2026-2004 https://www.cve.org/CVERecord?id=CVE-2026-2004 Référence CVE CVE-2026-2005 https://www.cve.org/CVERecord?id=CVE-2026-2005 Référence CVE CVE-2026-2006 https://www.cve.org/CVERecord?id=CVE-2026-2006 Référence CVE CVE-2026-22731 https://www.cve.org/CVERecord?id=CVE-2026-22731 Référence CVE CVE-2026-22732 https://www.cve.org/CVERecord?id=CVE-2026-22732 Référence CVE CVE-2026-22733 https://www.cve.org/CVERecord?id=CVE-2026-22733 Référence CVE CVE-2026-24281 https://www.cve.org/CVERecord?id=CVE-2026-24281 Référence CVE CVE-2026-24308 https://www.cve.org/CVERecord?id=CVE-2026-24308 Référence CVE CVE-2026-24880 https://www.cve.org/CVERecord?id=CVE-2026-24880 Référence CVE CVE-2026-25854 https://www.cve.org/CVERecord?id=CVE-2026-25854 Référence CVE CVE-2026-27171 https://www.cve.org/CVERecord?id=CVE-2026-27171 Référence CVE CVE-2026-27727 https://www.cve.org/CVERecord?id=CVE-2026-27727 Référence CVE CVE-2026-27830 https://www.cve.org/CVERecord?id=CVE-2026-27830 Référence CVE CVE-2026-27970 https://www.cve.org/CVERecord?id=CVE-2026-27970 Référence CVE CVE-2026-29145 https://www.cve.org/CVERecord?id=CVE-2026-29145 Référence CVE CVE-2026-29146 https://www.cve.org/CVERecord?id=CVE-2026-29146 Référence CVE CVE-2026-32635 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0621Multiples vulnérabilités dans les produits Atlassian

De multiples vulnérabilités ont été découvertes dans les produits Atlassian. Certaines d'entre elles permettent à un attaquant de provoquer une exécution de code arbitraire à distance, un déni de service à distance et une atteinte à la confidentialité des données.

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0556Multiples vulnérabilités dans les produits VMware

ecord?id=CVE-2026-22737 Référence CVE CVE-2026-22815 https://www.cve.org/CVERecord?id=CVE-2026-22815 Référence CVE CVE-2026-2297 https://www.cve.org/CVERecord?id=CVE-2026-2297 Référence CVE CVE-2026-2332 https://www.cve.org/CVERecord?id=CVE-2026-2332 Référence CVE CVE-2026-23949 https://www.cve.org/CVERecord?id=CVE-2026-23949 Référence CVE CVE-2026-24049 https://www.cve.org/CVERecord?id=CVE-2026-24049 Référence CVE CVE-2026-24051 https://www.cve.org/CVERecord?id=CVE-2026-24051 Référence CVE CVE-2026-24281 https://www.cve.org/CVERecord?id=CVE-2026-24281 Référence CVE CVE-2026-24308 https://www.cve.org/CVERecord?id=CVE-2026-24308 Référence CVE CVE-2026-24880 https://www.cve.org/CVERecord?id=CVE-2026-24880 Référence CVE CVE-2026-25645 https://www.cve.org/CVERecord?id=CVE-2026-25645 Référence CVE CVE-2026-25679 https://www.cve.org/CVERecord?id=CVE-2026-25679 Référence CVE CVE-2026-25854 https://www.cve.org/CVERecord?id=CVE-2026-25854 Référence CVE CVE-2026-25990 https://www.cve.org/CVERecord?id=CVE-2026-25990 Référence CVE CVE-2026-27135 https://www.cve.org/CVERecord?id=CVE-2026-27135 Référence CVE CVE-2026-27139 https://www.cve.org/CVERecord?id=CVE-2026-27139 Référence CVE CVE-2026-27140 https://www.cve.org/CVERecord?id=CVE-2026-27140 Référence CVE CVE-2026-27141 https://www.cve.org/CVERecord?id=

Official advisory
CERT-FR · French · CERTFR-2026-AVI-0418Multiples vulnérabilités dans Apache Tomcat

De multiples vulnérabilités ont été découvertes dans Apache Tomcat. Elles permettent à un attaquant de provoquer une atteinte à la confidentialité des données, une atteinte à l'intégrité des données et un contournement de la politique de sécurité.

Official advisory
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Fix not verified
Affected
11.0.0-M1 ≤ 11.0.18; 10.1.0-M1 ≤ 10.1.52; 9.0.0.M1 ≤ 9.0.115; 8.5.0 ≤ 8.5.100; 7.0.0 ≤ 7.0.109; < 7.0.0; 8.0.0-RC1 ≤ 8.0.53
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
No verified patch reference is present in the current structured sources. Check the vendor advisory before making a change.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 9 Apr 2026 · Last source change 10 Apr 2026, 18:33 UTC · CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CVE recordCVE.org · 5.2
CVSS sourceCISA ADP
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-21006
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD enriched

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates →

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-24880 · cve.blacktree.nl