CyberSecBulletin
CVE-2022-43551NVD status: Modified

https://github.com/curl/curl: Cleartext Transmission of Sensitive Information

CVE-2022-43551 is a high-severity cleartext transmission of sensitive information vulnerability in https://github.com/curl/curl, with a CVSS 3.1 base score of 7.5 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. Affected https://github.com/curl/curl versions: Fixed in curl 7.87.0. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 16.6% chance of exploitation within 30 days, which is in the top 2.94% of all scored CVEs.

Patch this week

EPSS places it among the vulnerabilities most likely to be exploited soon.

What to do

  1. Update SIMATIC S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5 or a later version.
  2. Update SIMATIC S7-1500 CPU 1518F-4 PN/DP MFP to V3.1.5 or a later version.
  3. Update SIPLUS S7-1500 CPU 1518-4 PN/DP MFP to V3.1.5 or a later version.
  4. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Https://github.com/curl/curlhttps://github.com/curl/curlFixed in curl 7.87.0Not stated
SiemensSIMATIC S7-1500 CPU 1518-4 PN/DP MFPV3.1.0 up to, but not including, V3.1.5V3.1.5
SiemensSIMATIC S7-1500 CPU 1518F-4 PN/DP MFPV3.1.0 up to, but not including, V3.1.5V3.1.5
SiemensSIPLUS S7-1500 CPU 1518-4 PN/DP MFPV3.1.0 up to, but not including, V3.1.5V3.1.5
HaxxCurl7.77.0 up to, but not including, 7.87.07.87.0
Fedora ProjectFedora37Not stated
NetAppActive Iq Unified ManagerNot specified in the recordNot stated
NetAppOncommand InsightNot specified in the recordNot stated
NetAppOncommand Workflow AutomationNot specified in the recordNot stated
NetAppSnapcenterNot specified in the recordNot stated
SplunkUniversal Forwarder8.2.0 up to, but not including, 8.2.12; 9.0.0 up to, but not including, 9.0.6; 9.1.08.2.12, 9.0.6

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Scope
UnchangedImpact stays within the vulnerable component.
Confidentiality
HighAll data handled by the component can be read.
Integrity
NoneNothing can be modified.
Availability
NoneAvailability is not affected.

Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N. Scored by NVD.

Scoring systemScoreSeverityScored by
CVSS 3.17.5HighNVD
CVSS 3.17.5HighCISA (ADP)

Official 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.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Cleartext Transmission of Sensitive Information

The product transmits sensitive or security-critical data in cleartext in a communication channel that can be sniffed by unauthorized actors.

How developers prevent this class of flaw

  • Before transmitting, encrypt the data using reliable, confidentiality-protecting cryptographic protocols.
  • When using web applications with SSL, use SSL for the entire session from login to logout, not just for the initial login page.
  • When designing hardware platforms, ensure that approved encryption algorithms (such as those recommended by NIST) protect paths from security critical data to trusted user applications.

More Cleartext Transmission of Sensitive Information vulnerabilities (CWE-319)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: poc, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Technical write-ups (may include proof of concept)

Other vulnerabilities in https://github.com/curl/curl

All https://github.com/curl/curl vulnerabilities

Recent Cleartext Transmission of Sensitive Information vulnerabilities

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