CVE-2023-23915: Medium severity IBM IBM® Engineering Requirements Management DOORS vulnerability
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.
Other sources
cURL libcurl could allow a remote attacker to obtain sensitive information, caused by a flaw in the HSTS function when multiple URLs are requested in parallel. By sniffing the network traffic, an attacker could exploit this vulnerability to obtain sensitive information, and use this information to launch further attacks against the affected system.
— IBM
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 recently completed transfer.
— Red Hat
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
redhat/curlto a version that resolves this vulnerability.Fixed in 7.88.0 - Configuration
Avoid performing multiple parallel transfers with curl (serialize transfers) until you have upgraded to redhat/curl 7.88.0, because the HSTS cache can be overwritten when transfers run in parallel.
curl (libcurl HSTS cache) parallel_transfers = disable (serialize transfers) - Compensating control
Limit exposure to network sniffing until systems are patched: restrict access to hosts performing HTTP transfers to trusted networks/IPs (firewall/ACL), apply network segmentation and monitoring, and avoid sending sensitive data over unencrypted HTTP.
Event History
Frequently Asked Questions
What is CVE-2023-23915?
CVE-2023-23915 is a vulnerability in curl <v7.88.0 that allows cleartext transmission of sensitive information, causing HSTS functionality to behave incorrectly when multiple URLs are requested in parallel.
How does CVE-2023-23915 affect me?
If you are using curl <v7.88.0 and requesting multiple URLs in parallel, this vulnerability could expose sensitive information transmitted over clear-text HTTP.
What is the severity of CVE-2023-23915?
The severity of CVE-2023-23915 is medium, with a CVSS score of 6.5.
How can I fix CVE-2023-23915?
To fix the CVE-2023-23915 vulnerability, you need to update curl to version 7.88.0 or later.
Where can I find more information about CVE-2023-23915?
You can find more information about CVE-2023-23915 at the following references: [Link 1](https://curl.se/docs/CVE-2023-23915.html), [Link 2](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=2170750), [Link 3](https://bugzilla.redhat.com/show_bug.cgi/show_bug.cgi?id=2170749).