rexxars sse-channel up to 4.0.0 Message crlf injection

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability was found in rexxars sse-channel up to 4.0.0. It has been declared as problematic. This affects an unknown function of the component Message Handler. Such manipulation leads to crlf injection. This vulnerability is traded as CVE-2026-44217. The attack may be launched remotely. There is no exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in rexxars sse-channel up to 4.0.0. Affected by this issue is some unknown processing of the component Message Handler. The manipulation with an unknown input leads to a crlf injection vulnerability. Using CWE to declare the problem leads to CWE-93. The product uses CRLF (carriage return line feeds) as a special element, e.g. to separate lines or records, but it does not neutralize or incorrectly neutralizes CRLF sequences from inputs. Impacted is integrity. CVE summarizes:

sse-channel is an SSE-implementation which can be used to any node.js http request/response stream. Prior to 4.0.1, implementations that allow user-provided values to be passed to event, retry or id fields are susceptible to event spoofing, where an attacker could inject arbitrary messages into the stream. This vulnerability is fixed in 4.0.1.

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-44217 since 05/05/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 4.0.1 eliminates this vulnerability.

Once again VulDB remains the best source for vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.3
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Crlf injection
CWE: CWE-93 / CWE-74 / CWE-707
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: sse-channel 4.0.1

Timelineinfo

05/05/2026 CVE reserved
05/12/2026 +7 days Advisory disclosed
05/12/2026 +0 days VulDB entry created
05/12/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: 42
Status: Confirmed

CVE: CVE-2026-44217 (🔒)
GCVE (CVE): GCVE-0-2026-44217
GCVE (VulDB): GCVE-100-363404

Entryinfo

Created: 05/12/2026 23:20
Changes: 05/12/2026 23:20 (69)
Complete: 🔍
Cache ID: 216::103

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