CVE-2022-43551: A vulnerability exists in curl <7.87.0 HSTS check that could be bypassed to trick it to keep using HTTP

Q: How urgent is CVE-2022-43551?

Priority 61/100. High severity; EPSS top 3%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

This week

HIGH 7.5REMOTEUPGRADEMITIGATEMITIGATE

CVE-2022-43551 is a high-severity flaw (CVSS 7.5) affecting curl, fedora, active iq unified manager. Below: why it ranks where it does, which versions are affected, what to do, and the exact commands.

A vulnerability exists in curl <7.87.0 HSTS check that could be bypassed to trick it to keep using HTTP. 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. However, the HSTS mechanism could be bypassed if the host name in the given URL first uses IDN characters that get replaced to ASCII counterparts as part of the IDN conversion. Like using the char

Why this priority

High severity
EPSS top 3%: very likely to be exploited
Public exploit reference
Remotely exploitable, no login, no user action

A fixed release or distro patch exists.

Risk facts

CVSS score	7.5 (High)
Attack vector	Network (remote)
Attack complexity	Low
Privileges needed	None
User interaction	None
EPSS exploit chance	16.6% (top 3%)
CISA exploited list	No
Weakness	CWE-319
Published	2022-12-23
Last modified	2026-10-14

Publisher (CNA): HackerOne · Vendor: fedoraproject · haxx · netapp

Last updated 2026-10-14 · Sources: CVE Program, NVD, CISA KEV, EPSS and vendor advisories · How we score

Am I affected?

Timeline

2022-12-23 15:15 UTCPublished CVE record published
2026-10-14 19:16 UTCUpdated Record last modified

haxx curl UPGRADE

Affected: >= 7.77.0 and < 7.87.0

Fixed in: 7.87.0

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 7.87.0 (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.

fedoraproject fedora MITIGATE

Affected: 37

Fixed in: no fixed release known

Safe to downgrade to: a release before 37

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 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 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 oncommand insight 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 oncommand-insight || rpm -q oncommand-insight || oncommand-insight --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

netapp oncommand workflow automation 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 oncommand-workflow-automation || rpm -q oncommand-workflow-automation || oncommand-workflow-automation --version

No fixed or unaffected release known

Apply the vendor mitigation from the advisory, disable the affected feature, or restrict network access.

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.

Quick answers

How do I fix CVE-2022-43551?

curl: upgrade to 7.87.0; fedora: mitigate or apply the listed mitigation; active iq unified manager: mitigate or apply the listed mitigation. Exact commands for each OS are on this page.

Is CVE-2022-43551 being exploited?

CVE-2022-43551 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-2022-43551 affect?

CVE-2022-43551 affects curl, fedora, active iq unified manager. Severity is high (CVSS 7.5). A vulnerability exists in curl <7.87.0 HSTS check that could be bypassed to trick it to keep using HTTP. Using its HSTS support, curl can be instructed to use HTTPS instead of using an insecure clear-text HTTP step even when HTTP is provide

How urgent is CVE-2022-43551?

Priority 61/100. High severity; EPSS top 3%: very likely to be exploited; Public exploit reference; Remotely exploitable, no login, no user action

Software pages

curl vulnerabilities

Related CVEs

CVE-2023-23915 MEDIUM 6.5 UPGRADE MITIGATE A cleartext transmission of sensitive information vulnerability exists in curl <v7.88.0 that could cause HSTS
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

References

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