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Full vulnerability report · 2025
CVE-2024-6827High confidence

HTTP Request Smuggling in benoitc/gunicorn

benoitc · benoitc/gunicorn

7.5HighCVSS 3.0
Recommended action
Within 7 days

High technical severity with public exploit material referenced by a structured source; 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.

1 package state
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 · standard archivegunicornUnder evaluationCanonical reports that the package might be affected and still needs evaluation or fixing.Not published in this feedCanonical record ↗Source updated 11 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-2025-6969

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 with public exploit material referenced by a structured source; prioritise exposed affected systems while verifying vendor guidance.

Fix not verified
01

What, why and how

Gunicorn version 21.2.0 does not properly validate the value of the 'Transfer-Encoding' header as specified in the RFC standards, which leads to the default fallback method of 'Content-Length,' making it vulnerable to TE.CL request smuggling. This vulnerability can lead to cache poisoning, data exposure, session manipulation, SSRF, XSS, DoS, data integrity compromise, security bypass, information leakage, and business logic abuse.

What

Gunicorn version 21.2.0 does not properly validate the value of the 'Transfer-Encoding' header as specified in the RFC standards, which leads to the default fallback method of 'Content-Length,' making it vulnerable to TE.CL request smuggling. This vulnerability can lead to cache poisoning, data exposure, session manipulation, SSRF, XSS, DoS, data integrity compromise, security bypass, information leakage, and business logic abuse.

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

Gunicorn version 21.2.0 does not properly validate the value of the 'Transfer-Encoding' header as specified in the RFC standards, which leads to the default fallback method of 'Content-Length,' making it vulnerable to TE.CL request smuggling. This vulnerability can lead to cache poisoning, data exposure, session manipulation, SSRF, XSS, DoS, data integrity compromise, security bypass, information leakage, and business logic abuse.

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.
Reference recorded

CISA Vulnrichment records proof-of-concept exploitation in its SSVC data. BlackTree has not independently executed or validated exploit material.

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:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Common Vulnerability Scoring System 3.0: 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.CHighConfidentiality impact: A successful attack can cause a major loss.INoneIntegrity impact: No direct loss is represented by this metric.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-444Public exploit reference
A

Official authority intelligence

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

BSI · German · WID-SEC-2025-0998IBM App Connect Enterprise Certified Container: Mehrere Schwachstellen

Ein Angreifer kann mehrere Schwachstellen in IBM App Connect Enterprise ausnutzen, um Dateien zu manipulieren, vertrauliche Informationen preiszugeben und einen Denial-of-Service-Zustand zu verursachen.

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0896Multiples vulnérabilités dans les produits IBM

ecord?id=CVE-2024-12801 Référence CVE CVE-2024-21538 https://www.cve.org/CVERecord?id=CVE-2024-21538 Référence CVE CVE-2024-38820 https://www.cve.org/CVERecord?id=CVE-2024-38820 Référence CVE CVE-2024-44906 https://www.cve.org/CVERecord?id=CVE-2024-44906 Référence CVE CVE-2024-47081 https://www.cve.org/CVERecord?id=CVE-2024-47081 Référence CVE CVE-2024-47535 https://www.cve.org/CVERecord?id=CVE-2024-47535 Référence CVE CVE-2024-55565 https://www.cve.org/CVERecord?id=CVE-2024-55565 Référence CVE CVE-2024-6484 https://www.cve.org/CVERecord?id=CVE-2024-6484 Référence CVE CVE-2024-6485 https://www.cve.org/CVERecord?id=CVE-2024-6485 Référence CVE CVE-2024-6827 https://www.cve.org/CVERecord?id=CVE-2024-6827 Référence CVE CVE-2024-6839 https://www.cve.org/CVERecord?id=CVE-2024-6839 Référence CVE CVE-2024-6844 https://www.cve.org/CVERecord?id=CVE-2024-6844 Référence CVE CVE-2024-6866 https://www.cve.org/CVERecord?id=CVE-2024-6866 Référence CVE CVE-2024-7598 https://www.cve.org/CVERecord?id=CVE-2024-7598 Référence CVE CVE-2025-1647 https://www.cve.org/CVERecord?id=CVE-2025-1647 Référence CVE CVE-2025-1767 https://www.cve.org/CVERecord?id=CVE-2025-1767 Référence CVE CVE-2025-22228 https://www.cve.org/CVERecord?id=CVE-2025-22228 Référence CVE CVE-2025-22233 https://www.cve.org/CVERecord?id=CVE-2025-2223

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0760Multiples vulnérabilités dans les produits IBM

CVERecord?id=CVE-2024-56201 Référence CVE CVE-2024-56326 https://www.cve.org/CVERecord?id=CVE-2024-56326 Référence CVE CVE-2024-56332 https://www.cve.org/CVERecord?id=CVE-2024-56332 Référence CVE CVE-2024-56339 https://www.cve.org/CVERecord?id=CVE-2024-56339 Référence CVE CVE-2024-57699 https://www.cve.org/CVERecord?id=CVE-2024-57699 Référence CVE CVE-2024-6484 https://www.cve.org/CVERecord?id=CVE-2024-6484 Référence CVE CVE-2024-6485 https://www.cve.org/CVERecord?id=CVE-2024-6485 Référence CVE CVE-2024-6762 https://www.cve.org/CVERecord?id=CVE-2024-6762 Référence CVE CVE-2024-6763 https://www.cve.org/CVERecord?id=CVE-2024-6763 Référence CVE CVE-2024-6827 https://www.cve.org/CVERecord?id=CVE-2024-6827 Référence CVE CVE-2024-7254 https://www.cve.org/CVERecord?id=CVE-2024-7254 Référence CVE CVE-2024-8184 https://www.cve.org/CVERecord?id=CVE-2024-8184 Référence CVE CVE-2024-9823 https://www.cve.org/CVERecord?id=CVE-2024-9823 Référence CVE CVE-2025-0755 https://www.cve.org/CVERecord?id=CVE-2025-0755 Référence CVE CVE-2025-1647 https://www.cve.org/CVERecord?id=CVE-2025-1647 Référence CVE CVE-2025-21756 https://www.cve.org/CVERecord?id=CVE-2025-21756 Référence CVE CVE-2025-21759 https://www.cve.org/CVERecord?id=CVE-2025-21759 Référence CVE CVE-2025-21887 https://www.cve.org/CVERecord?id=CVE-2025-21

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0627Multiples vulnérabilités dans les produits IBM

ecord?id=CVE-2023-32305 Référence CVE CVE-2023-43804 https://www.cve.org/CVERecord?id=CVE-2023-43804 Référence CVE CVE-2023-44270 https://www.cve.org/CVERecord?id=CVE-2023-44270 Référence CVE CVE-2023-45133 https://www.cve.org/CVERecord?id=CVE-2023-45133 Référence CVE CVE-2023-46298 https://www.cve.org/CVERecord?id=CVE-2023-46298 Référence CVE CVE-2024-1135 https://www.cve.org/CVERecord?id=CVE-2024-1135 Référence CVE CVE-2024-29041 https://www.cve.org/CVERecord?id=CVE-2024-29041 Référence CVE CVE-2024-52046 https://www.cve.org/CVERecord?id=CVE-2024-52046 Référence CVE CVE-2024-5629 https://www.cve.org/CVERecord?id=CVE-2024-5629 Référence CVE CVE-2024-6827 https://www.cve.org/CVERecord?id=CVE-2024-6827 Référence CVE CVE-2024-7254 https://www.cve.org/CVERecord?id=CVE-2024-7254 Référence CVE CVE-2025-21587 https://www.cve.org/CVERecord?id=CVE-2025-21587 Référence CVE CVE-2025-2900 https://www.cve.org/CVERecord?id=CVE-2025-2900 Référence CVE CVE-2025-30698 https://www.cve.org/CVERecord?id=CVE-2025-30698 Référence CVE CVE-2025-36097 https://www.cve.org/CVERecord?id=CVE-2025-36097 Référence CVE CVE-2025-4447 https://www.cve.org/CVERecord?id=CVE-2025-4447 Référence CVE CVE-2025-4565 https://www.cve.org/CVERecord?id=CVE-2025-4565 Gestion détaillée du document le 25 juillet 2025 Version initiale Alert

Official advisory
CERT-FR · French · CERTFR-2025-AVI-0512Multiples vulnérabilités dans les produits IBM

ord?id=CVE-2024-49761 Référence CVE CVE-2024-51744 https://www.cve.org/CVERecord?id=CVE-2024-51744 Référence CVE CVE-2024-52046 https://www.cve.org/CVERecord?id=CVE-2024-52046 Référence CVE CVE-2024-52798 https://www.cve.org/CVERecord?id=CVE-2024-52798 Référence CVE CVE-2024-53197 https://www.cve.org/CVERecord?id=CVE-2024-53197 Référence CVE CVE-2024-53382 https://www.cve.org/CVERecord?id=CVE-2024-53382 Référence CVE CVE-2024-56171 https://www.cve.org/CVERecord?id=CVE-2024-56171 Référence CVE CVE-2024-57965 https://www.cve.org/CVERecord?id=CVE-2024-57965 Référence CVE CVE-2024-6345 https://www.cve.org/CVERecord?id=CVE-2024-6345 Référence CVE CVE-2024-6827 https://www.cve.org/CVERecord?id=CVE-2024-6827 Référence CVE CVE-2024-7254 https://www.cve.org/CVERecord?id=CVE-2024-7254 Référence CVE CVE-2025-0917 https://www.cve.org/CVERecord?id=CVE-2025-0917 Référence CVE CVE-2025-0923 https://www.cve.org/CVERecord?id=CVE-2025-0923 Référence CVE CVE-2025-22868 https://www.cve.org/CVERecord?id=CVE-2025-22868 Référence CVE CVE-2025-22869 https://www.cve.org/CVERecord?id=CVE-2025-22869 Référence CVE CVE-2025-22870 https://www.cve.org/CVERecord?id=CVE-2025-22870 Référence CVE CVE-2025-24928 https://www.cve.org/CVERecord?id=CVE-2025-24928 Référence CVE CVE-2025-24970 https://www.cve.org/CVERecord?id=CVE-202

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
benoitc/gunicorn: unspecified ≤ latest
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 20 Mar 2025 · Last source change 15 Oct 2025, 12:50 UTC · CWE-444 · Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CVE recordCVE.org · 5.1
CVSS sourceCNA
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-2025-6969
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled

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-2024-6827 · cve.blacktree.nl