CVE-2026-87864

Enabling `CURLOPT_CRLF` causes curl to advertise the raw input byte count in the `IMAP APPEND {N}` literal while transmitting line-ending expanded data. The server reads only $N$ bytes for the payload, causing the remaining overflow bytes to be interpreted and executed as pipelined IMAP commands within the authenticated session.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.2 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://curl.se/docs/CVE-2026-87864.html
https://curl.se/docs/CVE-2026-87864.json
https://hackerone.com/reports/3972403
https://hackerone.com/reports/3972403

Configurations

No configuration.

History

30 Oct 2026, 12:16

Type	Values Removed	Values Added
References	~~() https://hackerone.com/reports/3972403 -~~	() https://hackerone.com/reports/3972403 -
CWE		CWE-130
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.1

20 Oct 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-20 21:17

Updated : 2026-10-30 12:16

NVD link : CVE-2026-87864

Mitre link : CVE-2026-87864

CVE.ORG link : CVE-2026-87864

JSON object : View

Products Affected

No product.

CWE

CWE-130

Improper Handling of Length Parameter Inconsistency

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"CWE-130"}]}], "descriptions": [{"lang": "en", "value": "Enabling `CURLOPT_CRLF` causes curl to advertise the raw input byte count in\nthe `IMAP APPEND {N}` literal while transmitting line-ending expanded data.\nThe server reads only $N$ bytes for the payload, causing the remaining\noverflow bytes to be interpreted and executed as pipelined IMAP commands\nwithin the authenticated session."}], "lastModified": "2026-10-30T12:16:46.137", "sourceIdentifier": "2499f714-1537-4658-8207-48ae4bb9eae9"}