CVE-2026-8458: wrong reuse for different services

mediumCVSS 6.5CVE-2026-8458

CSIRTS triage

Other

What: A medium severity vulnerability related to wrong reuse for different services.
Who is affected: Affected users of the impacted systems.
Urgency: Remediation is necessary due to the medium severity.
Action: Investigate and apply necessary mitigations.

AI-assisted analysis generated from the source advisory — verify against the original.

Details

Source: Microsoft Security Response Center (INTL · vendor-psirt · site)
Severity: medium — CVSS 6.5
Published: 2026-07-02
Exploitation: Not in CISA KEV at last sync

Original advisory: https://msrc.microsoft.com/update-guide/vulnerability/CVE-2026-8458

Exploitation outlook

EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.

Low exploitation riskCVE-2026-84580.54% 30-day exploitation probability — currently an unlikely target, but scores change as exploit code circulates. Riskier than 42% of all scored CVEs.

Referenced CVEs

CVE	CSIRTS overview	External
CVE-2026-8458	coverage & exploitation status	NVD · CVE.org

Same CVEs, other sources

How other CERTs, PSIRTs and databases cover the vulnerabilities in this advisory.

medium[UPDATE] [medium] cURL: Multiple vulnerabilitiescert-bund
mediumCVE-2026-8458: libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authe…nvd
unknownMultiple vulnerabilities in cURL and libcurl (June 24, 2026)cert-fr-avis

Recent advisories for wrong reuse for

A cluster of recent advisories against the same product widens the attack surface — attackers routinely chain freshly published CVEs on one product, so review these together.

mediumCVE-2026-8458: libcurl might in some circumstances reuse the wrong connection when asked to do Negotiate-authe…nvd · 2026-07-03
highCVE-2026-8286: wrong STARTTLS connection reusemsrc · 2026-07-02