CVE-2026-19931
MEDIUMDescription
A flaw in libcurl makes it wrongly reuse an HTTP connection setup for a given hostname using Negotiate authentication, when the initial request is done using empty credentials. This can make user B's request get sent over user A's previously authenticated connection.
How to fix
TridentStack Control can deploy fixes like this automatically across your Windows, macOS, and Linux fleet. See how it works
Remediation is compiled from vendor and distribution security advisories. Always confirm against the linked source for your exact version and platform.
CVSS v3 Vector
Exploitability
Impact
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:L/A:N
Exploit Intelligence
Moderate risk: more likely to be exploited than 65% of all known CVEs.
References
Related Vulnerabilities
Other CWE-488 vulnerabilities, ordered by exploit likelihood. View all
| CVE | Severity | CVSS | EPSS | Exploited | Fix |
|---|---|---|---|---|---|
| CVE-2024-38367 | High | 8.2 | 11% | - | Fix |
| CVE-2024-6162 | High | 7.5 | 1.7% | - | Fix |
| CVE-2026-80231 | Low | 3.7 | 0.9% | - | Fix |
| CVE-2025-1247 | High | 8.3 | 0.8% | - | - |
| CVE-2024-27935 | High | 7.2 | 0.7% | - | Fix |
| CVE-2024-27455 | Critical | 9.1 | 0.6% | - | - |
Common questions
How do I fix CVE-2026-19931?
Upgrade curl on debian unstable to 8.22.0~rc2-1 or later.
Is CVE-2026-19931 being actively exploited?
Not that we know of. CVE-2026-19931 is not in the CISA Known Exploited Vulnerabilities catalog. Its EPSS score of 1.2% is the estimated probability that it will be exploited in the next 30 days. That is higher than 65% of all scored CVEs.
How severe is CVE-2026-19931?
CVE-2026-19931 has a CVSS v3 base score of 6.5, rated moderate. CVSS rates the technical impact if the vulnerability is exploited, not how likely that is, so weigh it alongside the exploit-prediction score when you decide what to patch first.
What does CVE-2026-19931 affect?
Published advisories record a fix for curl (Debian). Only products with a sourced advisory are listed, so treat this as what we can cite rather than a complete inventory.
Embed a live status badge for CVE-2026-19931
Markdown
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This product uses NVD data but is not endorsed or certified by the NVD. EPSS scores courtesy of FIRST.org (https://www.first.org/epss). Source: CISA KEV Catalog. Data as of 2026-09-15.