PatchTheCVECVE-2023-23915: A cleartext transmission of sensitive information vulnerability exists in curl <v7.88.0 that could cause HSTS
42
This month
MEDIUM 6.5REMOTEUPGRADEMITIGATEDOWNGRADE
CVE-2023-23915 is a medium-severity flaw (CVSS 6.5) affecting curl, active iq unified manager, clustered data ontap. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.
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
Why this priority
- Remotely exploitable, no login, no user action
A fixed release or distro patch exists.
Risk facts
| CVSS score | 6.5 (Medium) |
| Attack vector | Network (remote) |
| Attack complexity | Low |
| Privileges needed | None |
| User interaction | None |
| EPSS exploit chance | 0.9% (top 41%) |
| CISA exploited list | No |
| Weakness | CWE-319 |
| Published | 2023-02-23 |
| Last modified | 2026-10-24 |
Last updated 2026-10-24 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score
Am I affected?
Timeline
- Published CVE record published
- Updated Record last modified
haxx curl UPGRADE
Affected: >= 7.77.0 and < 7.88.0
Fixed in: 7.88.0
Safe to downgrade to: a release before 7.77.0
1. Check installed version
apt-cache policy curl || rpm -q curl || curl --version
2. UPGRADE to 7.88.0 (Debian / Ubuntu)
sudo apt update && sudo apt install --only-upgrade curl
2. UPGRADE (RHEL / Amazon Linux / Fedora)
sudo dnf upgrade curl
Note
Distros often backport fixes without changing the version number. Confirm with the distro advisory or changelog.
3. If no update is available yet, DOWNGRADE to a release before 7.77.0 (Debian / Ubuntu)
apt-cache madison curl
sudo apt install curl=<VERSION_BEFORE_7.77.0>
sudo apt-mark hold curl
3. If no update is available yet, DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list curl
sudo dnf downgrade curl-<VERSION_BEFORE_7.77.0>
sudo dnf versionlock add curl
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
netapp active iq unified manager MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
1. Check installed version
apt-cache policy active-iq-unified-manager || rpm -q active-iq-unified-manager || active-iq-unified-manager --version
No fixed or unaffected release known
Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.
netapp clustered data ontap DOWNGRADE
Affected: 9.0
Fixed in: no fixed release known
Safe to downgrade to: a release before 9.0
1. Check installed version
apt-cache policy clustered-data-ontap || rpm -q clustered-data-ontap || clustered-data-ontap --version
2. No fixed release: DOWNGRADE to a release before 9.0 (Debian / Ubuntu)
apt-cache madison clustered-data-ontap
sudo apt install clustered-data-ontap=<VERSION_BEFORE_9.0>
sudo apt-mark hold clustered-data-ontap
2. No fixed release: DOWNGRADE (RHEL / Amazon Linux / Fedora)
dnf --showduplicates list clustered-data-ontap
sudo dnf downgrade clustered-data-ontap-<VERSION_BEFORE_9.0>
sudo dnf versionlock add clustered-data-ontap
Downgrade risk
Downgrading can break dependent software and may reopen older bugs. Read the distro advisory first and test on a non-production host.
After downgrade
Restart the service, and keep the package held until a fixed release ships.
netapp h300s firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
netapp h500s firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
netapp h700s firmware MITIGATE
Affected: all versions
Fixed in: no fixed release known
Safe to downgrade to: no unaffected older release
Check your OS release
cat /etc/os-release; uname -r
Debian / Ubuntu
sudo apt update && sudo apt full-upgrade
RHEL / Amazon Linux / Fedora
sudo dnf upgrade --refresh
Windows
Install the latest cumulative update from Windows Update
If no patch exists yet
OS downgrades are not safe. Apply the vendor mitigation from the advisory and restrict exposure.
Exact fixes by distribution
A distro patch exists: prefer upgrading over downgrading.
Fedora 46 · gnome-shell-extension-tiling-assistant · FIXED · 56-1.fc46 · FEDORA-2026-ebf66a5321 · source
sudo dnf upgrade --advisory=FEDORA-2026-ebf66a5321
Ubuntu 20.04 · curl · NOT AFFECTED
Ubuntu 22.04 · curl · FIXED · 7.81.0-1ubuntu1.8
sudo apt update && sudo apt install --only-upgrade curl
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' curl)" ge "7.81.0-1ubuntu1.8" && echo PATCHED || echo STILL-VULNERABLE
Debian 12 · curl · FIXED · 7.88.1-1
sudo apt update && sudo apt install --only-upgrade curl
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' curl)" ge "7.88.1-1" && echo PATCHED || echo STILL-VULNERABLE
Debian 13 · curl · FIXED · 7.88.1-1
sudo apt update && sudo apt install --only-upgrade curl
dpkg --compare-versions "$(dpkg-query -W -f='${Version}' curl)" ge "7.88.1-1" && echo PATCHED || echo STILL-VULNERABLE
RHEL 6 · curl · NOT AFFECTED
RHEL 7 · curl · NOT AFFECTED
RHEL 8 · curl · NOT AFFECTED
RHEL 9 · curl · NOT AFFECTED
Alpine 3.20 · curl · FIXED · curl-7.88.0-r0
apk add --upgrade curl
apk info -v curl
Alpine 3.21 · curl · FIXED · curl-7.88.0-r0
apk add --upgrade curl
apk info -v curl
Alpine 3.22 · curl · FIXED · curl-7.88.0-r0
apk add --upgrade curl
apk info -v curl
Alpine 3.23 · curl · FIXED · curl-7.88.0-r0
apk add --upgrade curl
apk info -v curl
sudo dnf update --advisory=ALAS2023-2023-114
sudo yum update --advisory=ALAS2-2023-1986
Verify at the official source NVD · CVE Program · Report a problem with this page
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Scores and fixes here are computed automatically from those and other public sources. Confirm with the vendor advisory before changing production systems.
Quick answers
How do I fix CVE-2023-23915?
curl: upgrade to 7.88.0; active iq unified manager: mitigate or apply the listed mitigation; clustered data ontap: downgrade or apply the listed mitigation. Exact commands for each OS are on this page.
Is CVE-2023-23915 being exploited?
CVE-2023-23915 is not on the CISA Known Exploited Vulnerabilities list at the time of the last update. Check again, as this can change.
What does CVE-2023-23915 affect?
CVE-2023-23915 affects curl, active iq unified manager, clustered data ontap. Severity is medium (CVSS 6.5). 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 t
How urgent is CVE-2023-23915?
Priority 42/100. Remotely exploitable, no login, no user action
Software pages
Related CVEs
- CVE-2023-27534 HIGH 8.8 UPGRADE MITIGATE A path traversal vulnerability exists in curl <8.0.0 SFTP implementation causes the tilde (~) character to be
- CVE-2023-28319 HIGH 7.5 UPGRADE UPGRADE A use after free vulnerability exists in curl <v8.1.0 in the way libcurl offers a feature to verify an SSH ser
- CVE-2023-28321 MEDIUM 5.9 UPGRADE MITIGATE An improper certificate validation vulnerability exists in curl <v8.1.0 in the way it supports matching of wil
- CVE-2022-43552 MEDIUM 5.9 UPGRADE UPGRADE A use after free vulnerability exists in curl <7.87.0
- CVE-2023-23916 MEDIUM 6.5 UPGRADE MITIGATE An allocation of resources without limits or throttling vulnerability exists in curl <v7.88.0 based on the "ch