CVE-2026-19931

Sunday, September 06, 2026

N/A

Summary

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.

Affected Software

Vendor	Product	Version Range	Status
curl	curl	`8.21.0 <= 8.21.0`	affected
curl	curl	`8.20.0 <= 8.20.0`	affected
curl	curl	`8.19.0 <= 8.19.0`	affected
curl	curl	`8.18.0 <= 8.18.0`	affected
curl	curl	`8.17.0 <= 8.17.0`	affected
curl	curl	`8.16.0 <= 8.16.0`	affected
curl	curl	`8.15.0 <= 8.15.0`	affected
curl	curl	`8.14.1 <= 8.14.1`	affected
curl	curl	`8.14.0 <= 8.14.0`	affected
curl	curl	`8.13.0 <= 8.13.0`	affected
curl	curl	`8.12.1 <= 8.12.1`	affected
curl	curl	`8.12.0 <= 8.12.0`	affected
curl	curl	`8.11.1 <= 8.11.1`	affected
curl	curl	`8.11.0 <= 8.11.0`	affected
curl	curl	`8.10.1 <= 8.10.1`	affected
curl	curl	`8.10.0 <= 8.10.0`	affected
curl	curl	`8.9.1 <= 8.9.1`	affected
curl	curl	`8.9.0 <= 8.9.0`	affected
curl	curl	`8.8.0 <= 8.8.0`	affected
curl	curl	`8.7.1 <= 8.7.1`	affected
curl	curl	`8.7.0 <= 8.7.0`	affected
curl	curl	`8.6.0 <= 8.6.0`	affected
curl	curl	`8.5.0 <= 8.5.0`	affected
curl	curl	`8.4.0 <= 8.4.0`	affected
curl	curl	`8.3.0 <= 8.3.0`	affected
curl	curl	`8.2.1 <= 8.2.1`	affected
curl	curl	`8.2.0 <= 8.2.0`	affected
curl	curl	`8.1.2 <= 8.1.2`	affected
curl	curl	`8.1.1 <= 8.1.1`	affected
curl	curl	`8.1.0 <= 8.1.0`	affected
curl	curl	`8.0.1 <= 8.0.1`	affected
curl	curl	`8.0.0 <= 8.0.0`	affected
curl	curl	`7.88.1 <= 7.88.1`	affected
curl	curl	`7.88.0 <= 7.88.0`	affected
curl	curl	`7.87.0 <= 7.87.0`	affected
curl	curl	`7.86.0 <= 7.86.0`	affected
curl	curl	`7.85.0 <= 7.85.0`	affected
curl	curl	`7.84.0 <= 7.84.0`	affected
curl	curl	`7.83.1 <= 7.83.1`	affected
curl	curl	`7.83.0 <= 7.83.0`	affected
curl	curl	`7.82.0 <= 7.82.0`	affected
curl	curl	`7.81.0 <= 7.81.0`	affected
curl	curl	`7.80.0 <= 7.80.0`	affected
curl	curl	`7.79.1 <= 7.79.1`	affected
curl	curl	`7.79.0 <= 7.79.0`	affected
curl	curl	`7.78.0 <= 7.78.0`	affected
curl	curl	`7.77.0 <= 7.77.0`	affected
curl	curl	`7.76.1 <= 7.76.1`	affected
curl	curl	`7.76.0 <= 7.76.0`	affected
curl	curl	`7.75.0 <= 7.75.0`	affected
curl	curl	`7.74.0 <= 7.74.0`	affected
curl	curl	`7.73.0 <= 7.73.0`	affected
curl	curl	`7.72.0 <= 7.72.0`	affected
curl	curl	`7.71.1 <= 7.71.1`	affected
curl	curl	`7.71.0 <= 7.71.0`	affected
curl	curl	`7.70.0 <= 7.70.0`	affected
curl	curl	`7.69.1 <= 7.69.1`	affected
curl	curl	`7.69.0 <= 7.69.0`	affected
curl	curl	`7.68.0 <= 7.68.0`	affected
curl	curl	`7.67.0 <= 7.67.0`	affected
curl	curl	`7.66.0 <= 7.66.0`	affected
curl	curl	`7.65.3 <= 7.65.3`	affected
curl	curl	`7.65.2 <= 7.65.2`	affected
curl	curl	`7.65.1 <= 7.65.1`	affected
curl	curl	`7.65.0 <= 7.65.0`	affected
curl	curl	`7.64.1 <= 7.64.1`	affected

Weaknesses

CWE-488 Exposure of Data Element to Wrong Session

References

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