Reference page — cumulative record through Tuesday, October 6, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-8458

CVE-2026-8458MEDIUM

curl curl — wrong reuse for different services

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   L   N  U  N  H  N    6.5   .0037   28.8     —

AFFECTED
  Product  Versions                                    Fixed
  curl     7.43.0 –                                    —
  curl     97c272e5d173ad5f706443e2477f0a84f0044edd –  —
  curl     8.20.0 –                                    —

TIMELINE
  May 13  Reserved by curl
  Jul 3   EXPLOIT PUBLISHED — CVE-2026-8458 (curl). Public exploit reference added.
  Jul 3   Published (CNA: curl)
  Sep 15  EXPLOIT PUBLISHED — CVE-2026-8458 (curl). Public exploit reference added.

CWE-488 · CNA: curl · CVSS v3.1 · 3 references · NVD status: Modified

Description

libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authenticated ones, even when they are set to use different "services". libcurl features a pool of recent connections so that subsequent requests can reuse an existing connection to avoid overhead. When reusing a connection a range of criteria must be met. Due to a logical error in the code, a request that was issued by an application could wrongfully reuse an existing connection to the same server that was authenticated using different services.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
May 13, 2026	Reserved	Reserved by curl
July 3, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-8458 (curl). Public exploit reference added.
July 3, 2026	Published	Published (CNA: curl)
September 15, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-8458 (curl). Public exploit reference added.

Affected

Affected products and packages — 3 rows
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
curl	curl	—	7.43.0	—
curl	curl	—	97c272e5d173ad5f706443e2477f0a84f0044edd	—
curl	curl	—	8.20.0	—

Weaknesses

CWE-488

References (3)

https://curl.se/docs/CVE-2026-8458.html [Patch, Vendor Advisory]
https://curl.se/docs/CVE-2026-8458.json [Vendor Advisory]
https://hackerone.com/reports/3721183 [Exploit, Issue Tracking, Third Party Advisory]

Authoritative record: CVE-2026-8458 at cve.org

Vendors: curl

Weaknesses: CWE-488

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-8458 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Tuesday, October 6, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.