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TI-2025-40874 Aliases CVE-2025-66442GHSA-56v8-wv3m-qgg6

In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and…

Priority LOW 23CWE-385Published · Updated

Key facts

Attack vector
Local
Privileges required
None
User interaction
None
Attack complexity
High
Impact type
—
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA.

Summary

In Mbed TLS through 4.0.0, there is a compiler-induced timing side channel (in RSA and CBC/ECB decryption) that only occurs with LLVM's select-optimize feature. TF-PSA-Crypto through 1.0.0 is also affected.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0028 20th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:*up to 4.0.0VulnerableArm
cpe:2.3:a:arm:tf-psa-crypto:*:*:*:*:*:*:*:*up to 1.0.0VulnerableArm
  • cpe:2.3:a:arm:mbed_tls:*:*:*:*:*:*:*:* Versions up to 4.0.0 Vulnerable ·Arm
  • cpe:2.3:a:arm:tf-psa-crypto:*:*:*:*:*:*:*:* Versions up to 1.0.0 Vulnerable ·Arm

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat's page for this CVE →

Not affected: 1 product
  • Red Hat

Timeline

  1. 2026-10-02 Threatist record created from CVE-2025-66442
  2. 2026-10-03 Alias added: GHSA-56v8-wv3m-qgg6

References

Advisory 2

Other 2

  • TI-2023-28736 An issue was discovered in Mbed TLS through 3.5.1. CVSS 3.1HIGH 7.5
  • TI-2021-19505 A Denial of Service vulnerability exists in mbed TLS 3.0.0 and earlier in the… CVSS 3.1HIGH 7.5
  • TI-2025-32620 Mbed TLS before 3.6.4 has a race condition in AESNI detection if certain compiler… CVSS 3.1HIGH 7.8
  • TI-2022-22925 An issue was discovered in Mbed TLS before 2.28.2 and 3.x before 3.3.0. CVSS 3.1CRITICAL 9.8
  • TI-2018-00445 Out-of-bounds write in ARM mbed TLS before 1.3.22, before 2.1.10, and before 2.7.0 CVSS 3.0CRITICAL 9.8
  • TI-2026-27113 An issue was discovered in Mbed TLS versions from 2.19.0 up to 3.6.5, Mbed TLS 4.0.0. CVSS 3.1CRITICAL 9.8
See all 50 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences