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CVE-2026-6733

undici vulnerable to HTTP response queue poisoning via keep-alive socket reuse

CVSS score

3.7

EPSS probability

%0.3

Risk score

0.0

Published

4 mo ago

Official patch verified

Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-6733 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

## Impact Undici's HTTP/1.1 client is vulnerable to response queue poisoning on reused keep-alive sockets. An attacker-controlled upstream server can inject an unsolicited HTTP/1.1 response onto an idle socket after a request completes. When the client dispatches the next request on that socket, it associates the injected response with the new request, causing responses to be delivered to the wrong requests. This requires an attacker-controlled or compromised upstream HTTP/1.1 server and keep-alive connection reuse. ## Patches Upgrade to undici v6.27.0, v7.28.0 or v8.5.0. ## Workarounds Disable keep-alive connection reuse by setting `keepAliveTimeout: 0` on the Client or Pool.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-6733 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1npmundici View
2npmundici View
3npmundici View
4npmundici View
5npmundici View
6npmundici View
Total affected vendors: 1|Products: 6

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
3.7CVSS 3.x—Vector not publishedGitHub Advisory
0.0CVSS 4.0—Vector not publishedGitHub Advisory

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

6 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

gitlabnpm/undici6.27.0

GitLab Advisory düzeltilmiş sürüm: 6.27.0

gitlabnpm/undici7.28.0

GitLab Advisory düzeltilmiş sürüm: 7.28.0

gitlabnpm/undici8.5.0

GitLab Advisory düzeltilmiş sürüm: 8.5.0

gitlab

Upgrade to versions 6.27.0, 7.28.0, 8.5.0 or above.

osvundici6.27.0

OSV düzeltilmiş sürüm: 6.27.0

osvundici7.28.0

OSV düzeltilmiş sürüm: 7.28.0

osvundici8.5.0

OSV düzeltilmiş sürüm: 8.5.0

canonical

Upgrade to versions 6.27.0, 7.28.0, 8.5.0 or above.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-6733 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-6733 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsGerekmiyor
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

3.7 / 10
Attack VectorNetworkComplexityHighPrivilegesNoneUser Interact.NoneConfidentialityHighIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N
Attack VectorNetwork
Attack ComplexityHigh
Privileges RequiredNone required
User InteractionNone required
Confidentiality (Gizlilik)High
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama doğrulandı

6 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

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Weakness Type (CWE & CAPEC)

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