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Public proof of conceptFix available

CVE-2022-43551

A public proof of concept exists; no exploitation attested.

  • Published2022-12-23
  • Fixed in9.0.6 · 8.2.12
  • WeaknessCWE-319

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

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 character UTF-8 U+3002 (IDEOGRAPHIC FULL STOP) instead of the common ASCII full stop (U+002E) `.`. Then in a subsequent request, it does not detect the HSTS state and makes a clear text transfer. Because it would store the info IDN encoded but look for it IDN decoded.

Timeline

dates in UTC
  1. 2022-12-2315:15CVE publishedNVD

Versions per branch

NVD
Splunk universal forwarder
BranchAffectedFixed in
9.0≥ 9.0.0, < 9.0.69.0.6
8.2≥ 8.2.0, < 8.2.128.2.12
9.1= 9.1.0no fix published
Fedoraproject fedora
BranchAffectedFixed in
37.x= 37no fix published
Haxx curl
BranchAffectedFixed in
7.x≥ 7.77.0, < 7.87.07.87.0

4 more products in the sources.

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Products declared by the CNA1 product

As hackerone, the CNA that assigned this CVE, declared them in the CVE record; versions as written.

  • https://github.com/curl/curl
    Affected
    • = Fixed in curl 7.87.0no fix stated

Source: the CNA record (CVE Program), © The MITRE Corporation,CVE Terms of UseCVE recordupdated 2023-10-11

Distribution builds and vendor advisories

Packages from OSV.dev and products from the vendors' CSAF advisories.

version not verifiedVersions not verified: read as OSV.dev and the vendors publish them, not checked against each vendor's release list.

Packages

  • cmakeAzure Linux:3all versions · fixed in 3.21.4-10
  • cmakeAzure Linux:2all versions · fixed in 3.21.4-3
  • curlWolfiall versions · fixed in 7.87.0-r0
  • curlUbuntu:22.04:LTSall versions · fixed in 7.81.0-1ubuntu1.7
  • curlUbuntu:20.04:LTSall versions · fixed in 7.68.0-1ubuntu2.15
  • curlUbuntu:18.04:LTSall versions · fixed in 7.58.0-2ubuntu3.22
  • curlSUSE:Linux Enterprise Module for Basesystem 15 SP4all versions · fixed in 7.79.1-150400.5.12.1
  • curlSUSE:Linux Enterprise Micro 5.3all versions · fixed in 7.79.1-150400.5.12.1

45 more package ranges on OSV.dev

Vendor advisories

  • CVE-2022-43551 Red Hat Product Security12 products fixed · 8 known affected

    curl: HSTS bypass via IDN

    curl as a component of Red Hat Enterprise Linux 6 · curl.src as a component of Red Hat Enterprise Linux 6 · libcurl as a component of Red Hat Enterprise Linux 6 · +5 more

  • ICSA-23-348-10 CISA5 known affected

    Siemens SIMATIC S7-1500

    SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) · +2 more

  • SSA-398330 Siemens ProductCERT5 known affected

    SSA-398330: Vulnerabilities in the additional GNU/Linux subsystem of the SIMATIC S7-1500 CPU 1518(F)-4 PN/DP MFP >= V3.1.0 and < V3.1.5

    SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AB0) >= V3.1.0 < V3.1.5 · SIMATIC S7-1500 CPU 1518-4 PN/DP MFP (6ES7518-4AX00-1AC0) >= V3.1.0 < V3.1.5 · SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP (6ES7518-4FX00-1AB0) >= V3.1.0 < V3.1.5 · +2 more

  • RHSA-2023:3354 Red Hat Product Security11 products fixed

    Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.51 SP2 security update

  • RHSA-2023:3355 Red Hat Product Security1 product fixed

    Red Hat Security Advisory: Red Hat JBoss Core Services Apache HTTP Server 2.4.51 SP2 security update

  • ICSA-23-131-05 CISA1 known affected

    Siemens SINEC NMS Third-Party

    SINEC NMS

1 more advisory

Full record on NVD

Fix

  1. Update Splunk universal forwarder to 9.0.6 · 8.2.12
  2. Vendor fix CISA ICSA-23-348-10 · 5 productsUpdate to V3.1.5 or later version
  3. Vendor fix Siemens ProductCERT SSA-398330 · 1 productUpdate to V3.1.5 or later version
  4. Vendor fix Red Hat Product Security RHSA-2023:3354 · 11 productsFor details on how to apply this update, which includes the changes described in this advisory, refer to: https://access.redhat.com/articles/11258 Applications using the APR libraries, such as httpd, must be restarted for this update to take effect. After installing the updated packages, the http…
  5. Vendor fix Red Hat Product Security RHSA-2023:3355 · 1 productBefore applying this update, make sure all previously released errata relevant to your system have been applied. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
  6. Vendor fix CISA ICSA-23-131-05 · 1 productUpdate to V1.0.3.1 or later version
  7. Vendor fix Siemens ProductCERT SSA-892048 · 1 productUpdate to V1.0.3.1 or later version

Detection

Nuclei template
none so far
ProjectDiscovery
Exploit-DB
no entry
Exploit-DB
Proof of concept
Metasploit modules
none listed
Metasploit Framework

Sources

Identifiers

Technical details

CVSS v3 Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Published
2022-12-23
Last Modified
2026-10-14
NVD status
Modified
GitHub Advisory
GHSA-25m2-mpq4-29vh

Frequently asked questions

What is CVE-2022-43551?

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 character UTF-8 U+3002 (IDEOGRAPHIC FULL STOP) instead of the common ASCII full stop (U+002E) `.`. Then in a subsequent request, it does not detect the HSTS state and makes a clear text transfer. Because it would store the info IDN encoded but look for it IDN decoded.

Is CVE-2022-43551 actively exploited?

A proof-of-concept exploit exists for CVE-2022-43551, but active exploitation has not been confirmed at this time.

What is the CVSS score for CVE-2022-43551?

CVE-2022-43551 has a CVSS v3 base score of 7.5 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

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