CVE-2026-42874

Microdot is a minimalistic Python web framework. Prior to 2.6.1, the Response.set_cookie() method does not sanitize its string arguments, and in particular will not detect the presence of the \r\n sequence in them. This can be a potential source of header injection attacks. For a header injection attack through this issue to be possible, an attacker must first infiltrate the client (for example through an independent XSS attack), so that it can send malicious information that is destined to be stored in a cookie by the server on behalf of the victim. An attacker that infiltrates one client can only orchestrate a header injection attack for that client, all other clients that were not infiltrated are safe. This vulnerability is fixed in 2.6.1.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/miguelgrinberg/microdot/blob/main/CHANGES.md
https://github.com/miguelgrinberg/microdot/commit/99b281b45faef8472410f2d56bfef496dfbd95d5
https://github.com/miguelgrinberg/microdot/security/advisories/GHSA-7wc8-wvc4-m498

Configurations

No configuration.

History

11 May 2026, 20:25

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-05-11 20:25

Updated : 2026-06-17 10:48

NVD link : CVE-2026-42874

Mitre link : CVE-2026-42874

CVE.ORG link : CVE-2026-42874

JSON object : View

Products Affected

No product.

CWE

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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