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CVE-2026-61642

Squid Request Smuggling in HTTP Transfer-Encoding

CVSS score

7.7

EPSS probability

—

Risk score

0.8

Published

14 h ago

Patch status has not yet been verified

Resmî kaynaklarda yeterli kanıt bulunamadı. Bu sonuç “yama yok” anlamına gelmez.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2026-61642 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

Squid is a caching proxy for the Web. From 3.3.0.1 to before 7.6, due to an improper enforcement of behavioral workflow bug, Squid is vulnerable to a Request Smuggling attack against HTTP/1.1 Transfer-Encoding. HTTP header parsing (`src/HttpHeader.cc`) accepted the bare` Transfer-Encoding:` identity form, which the HTTP specification prohibits because any transfer coding must be wrapped within chunked encoding. This problem allows a trusted client to perform an HTTP Request Smuggling attack when HTTP/1.1 is used, bypassing security mechanisms that may be in place between attacker and Squid. When there is an HTTP cache operating prior to the affected Squid, this Request Smuggling attack also allows the attacker to poison that web cache and store arbitrary malicious content at any URL for delivery to other clients' future requests. This issue is fixed in version 7.6.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-61642 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1squid-cachesquid View
Total affected vendors: 1|Products: 1

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
7.7CVSS V3_1HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:NCVE CNA
7.7CVSS V31HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:NNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Patch status unknown

İncelenen resmî kaynaklarda yama durumu doğrulanamadı. Bu sonuç “yama yok” anlamına gelmez.

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Until a patch is confirmed, follow the vendor advisory; do not read an unknown status as “no patch”.
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-2026-61642 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-2026-61642 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsLow
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

7.7 / 10
Attack VectorNetworkComplexityLowPrivilegesLowUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityNone

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:H/A:N
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow privileges
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)None

Yama durumu bilinmiyor

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Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

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