Answer in brief
CVE-2026-19931 records a Unknown severity vulnerability in Negotiate ambient user conn reuse. The current sources do not mark it as known exploited. The current feed maps curl/curl (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps curl/curl (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| curl/curlgeneric | 8.21.0 || 8.20.0 || 8.19.0 || 8.18.0 || 8.17.0 || 8.16.0 || 8.15.0 || 8.14.1 || 8.14.0 || 8.13.0 || 8.12.1 || 8.12.0 || 8.11.1 || 8.11.0 || 8.10.1 || 8.10.0 || 8.9.1 || 8.9.0 || 8.8.0 || 8.7.1 || 8.7.0 || 8.6.0 || 8.5.0 || 8.4.0 || 8.3.0 || 8.2.1 || 8.2.0 || 8.1.2 || 8.1.1 || 8.1.0 || 8.0.1 || 8.0.0 || 7.88.1 || 7.88.0 || 7.87.0 || 7.86.0 || 7.85.0 || 7.84.0 || 7.83.1 || 7.83.0 || 7.82.0 || 7.81.0 || 7.80.0 || 7.79.1 || 7.79.0 || 7.78.0 || 7.77.0 || 7.76.1 || 7.76.0 || 7.75.0 || 7.74.0 || 7.73.0 || 7.72.0 || 7.71.1 || 7.71.0 || 7.70.0 || 7.69.1 || 7.69.0 || 7.68.0 || 7.67.0 || 7.66.0 || 7.65.3 || 7.65.2 || 7.65.1 || 7.65.0 || 7.64.1 | Not reported |
Published upstream
Sep 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Sep 6, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Sep 6, 2026
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.
Quoted source text, attributed separately from HOL analysis.