---
id: CVE-2023-23915
title: >-
  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
summary: >-
  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
  instructe…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N'
cwe:
  - CWE-319
vendor: haxx
product: curl
affected:
  - 'curl >= 7.77.0, < 7.88.0'
  - active_iq_unified_manager
  - clustered_data_ontap = 9.0
  - h300s_firmware
  - h500s_firmware
  - h700s_firmware
  - h410s_firmware
  - 'universal_forwarder >= 8.2.0, < 8.2.12'
  - 'universal_forwarder >= 9.0.0, < 9.0.6'
  - universal_forwarder = 9.1.0
patched:
  - curl 7.88.0
  - universal_forwarder 9.0.6
published: '2023-02-23'
updated: '2026-10-14'
sourceUpdated: '2026-10-14T23:17:14.250'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2023-23915'
references:
  - url: 'https://hackerone.com/reports/1826048'
    label: support@hackerone.com
  - url: 'https://security.gentoo.org/glsa/202310-12'
    label: support@hackerone.com
  - url: 'https://security.netapp.com/advisory/ntap-20230309-0006/'
    label: support@hackerone.com
  - url: 'https://hackerone.com/reports/1826048'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.gentoo.org/glsa/202310-12'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://security.netapp.com/advisory/ntap-20230309-0006/'
    label: af854a3a-2127-422b-91ae-364da2661108
  - url: 'https://cert-portal.siemens.com/productcert/html/ssa-398330.html'
    label: 0b142b55-0307-4c5a-b3c9-f314f3fb7c5e
tags:
  - nvd
  - cve.org
epss: 0.00861
epssPercentile: 0.57659
ingestedAt: '2026-10-15T00:02:07.127Z'
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2025-06-03T18:46:29.585636Z'
---

## Overview

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.

## Affected

- `curl >= 7.77.0, < 7.88.0`
- `active_iq_unified_manager`
- `clustered_data_ontap = 9.0`
- `h300s_firmware`
- `h500s_firmware`
- `h700s_firmware`
- `h410s_firmware`
- `universal_forwarder >= 8.2.0, < 8.2.12`
- `universal_forwarder >= 9.0.0, < 9.0.6`
- `universal_forwarder = 9.1.0`

## Remediation

Upgrade past the affected range:

- `curl 7.88.0`
- `universal_forwarder 9.0.6`