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CVE-2024-2379 curl CVE debrief

libcurl, when built with wolfSSL, contains a flaw in its QUIC connection handling where certificate verification is incorrectly skipped under specific error conditions. If an application requests an unknown or unsupported cipher or curve, the resulting error path fails to perform certificate validation and returns a success status, effectively ignoring certificate problems. This vulnerability affects Siemens SINEC NMS, which incorporates the vulnerable libcurl component. The issue was published on November 12, 2024, with a CVSS 3.1 score of 4.3 (Medium severity). The vulnerability requires network access and low attack complexity, with the potential for integrity impact if an attacker can manipulate cipher/curve selection to bypass certificate validation in QUIC connections.

Vendor
curl
Product
SINEMA Remote Connect Client
CVSS
MEDIUM 4.3
CISA KEV
Not listed in stored evidence
Original CVE published
2024-09-10
Original CVE updated
2024-09-10
Advisory published
2024-09-10
Advisory updated
2024-09-10

Who should care

Organizations operating Siemens SINEC NMS for industrial network management, particularly those with QUIC-enabled connections or deployments using wolfSSL-backed libcurl. Security teams responsible for OT/ICS environments should prioritize patching given the certificate verification bypass risk. Network administrators managing encrypted communications in industrial control systems should verify cipher configurations and apply available updates.

Technical summary

The vulnerability exists in libcurl's QUIC implementation when compiled with wolfSSL. During QUIC connection establishment, if the application specifies an unknown or invalid cipher or curve, the error handling path incorrectly returns success without completing certificate verification. This logic flaw causes libcurl to report a successful connection despite unverified peer certificates, breaking the security guarantees of TLS. The issue is specific to QUIC connections and does not affect traditional TCP-based TLS connections. The vulnerability has been addressed in updated versions of SINEC NMS (V3.0 SP1+).

Defensive priority

medium

Recommended defensive actions

  • Upgrade Siemens SINEC NMS to V3.0 SP1 or later version to address the vulnerable libcurl component
  • Review network segmentation for SINEC NMS deployments to limit exposure of QUIC connections
  • Monitor for anomalous QUIC connection attempts that may indicate exploitation attempts
  • Verify TLS/QUIC cipher and curve configurations to avoid triggering the vulnerable error path
  • Apply defense-in-depth practices for industrial control systems as recommended by CISA

Evidence notes

The vulnerability description is sourced from CISA CSAF advisory ICSA-24-319-04, which references Siemens security advisory SSA-331112. The affected product is confirmed as Siemens SINEC NMS with vendor fix available in V3.0 SP1 or later.

Official resources

2024-11-12