CVE-2023-23915

Plain English Summary

AI-powered analysis for quick understanding

This vulnerability allows an attacker to potentially intercept sensitive information during data transfers because the curl tool may fail to upgrade certain HTTP requests to secure HTTPS when multiple requests are made at the same time. This issue occurs only when using curl versions prior to 7.88.0 and can lead to unprotected data being sent over the internet instead of the intended secure connection.

Technical Description

A cleartext transmission of sensitive information vulnerability exists in curl <v7.88.0 that could cause HSTS functionality to behave incorrectly when multiple URLs are requested in parallel. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP step even when HTTP is provided in the URL. This HSTS mechanism would however surprisingly fail when multiple transfers are done in parallel as the HSTS cache file gets overwritten by the most recentlycompleted transfer. A later HTTP-only transfer to the earlier host name would then *not* get upgraded properly to HSTS.

CVSS Vector Analysis

Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredNone
User InteractionNone
Confidentiality ImpactLow
Integrity ImpactLow
Availability ImpactNone
ScopeUnchanged

Vector String

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N

Exploit Resources

Search for proof-of-concept code and exploit modules

Official References

Est. Bounty
$931($500-$1K)
Vendor Response
Grade FPatched in 1086 days

Quick Information

Published

Feb 23, 2023

about 3 years ago

Last Modified

Feb 13, 2026

about 2 months ago

Vendor

haxx

Product

curl

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