CVE-2026-87864
highEnabling `CURLOPT_CRLF` causes curl to advertise the raw input byte count in the `IMAP APPEND {N}` literal while transmitting line-ending expanded data.
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
8.1
8.1 (CVSS v3.1)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H Severity source: NVD CVSS v3.1 (134c704f-9b21-4f2e-91b3-4a467353bcc0)
Timeline (UTC)
Published: 2026-10-20 21:17
Modified: 2026-10-30 12:16
NVD status: Awaiting Analysis
Last synced 1 day ago
Verified against the source API 2026-11-03 07:34 UTC
Exploitation
Not listed in CISA KEV (as of last catalog sync)
Absence from KEV does not mean a CVE is not exploited. Exploitation status: unknown (no authoritative evidence in our sources).
Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://curl.se/docs/CVE-2026-87864.html 2499f714-1537-4658-8207-48ae4bb9eae9
- https://curl.se/docs/CVE-2026-87864.json 2499f714-1537-4658-8207-48ae4bb9eae9
- https://hackerone.com/reports/3972403 2499f714-1537-4658-8207-48ae4bb9eae9
- https://hackerone.com/reports/3972403 134c704f-9b21-4f2e-91b3-4a467353bcc0
Data sources
NVD CVE API 2.0 — fetched 2026-11-03 07:34 UTC · record ↗

