CVE-2023-40271

Exp

In Trusted Firmware-M through TF-Mv1.8.0, for platforms that integrate the CryptoCell accelerator, when the CryptoCell PSA Driver software Interface is selected, and the Authenticated Encryption with Associated Data Chacha20-Poly1305 algorithm is used, with the single-part verification function (defined during the build-time configuration phase) implemented with a dedicated function (i.e., not relying on usage of multipart functions), the buffer comparison during the verification of the authentication tag does not happen on the full 16 bytes but just on the first 4 bytes, thus leading to the possibility that unauthenticated payloads might be identified as authentic. This affects TF-Mv1.6.0, TF-Mv1.6.1, TF-Mv1.7.0, and TF-Mv1.8.

Published: 2023-09-08 Last update: 2026-06-05 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2023-40271 is rated Exploit Available (53.5/100): CVSS High severity, with low exploitation likelihood (EPSS 0.32%). 1 public exploit reference(s) are indexed (Exploit-DB). Public exploits are available—assess exposure, apply mitigations, and prioritize patching.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Public exploit references (Exploit-DB) for CVE-2023-40271

EDB-ID Source Kind Published Link
— nvd_ref exploit_tag Exploit-DB ↗

Exploit prediction scoring system (EPSS) score for CVE-2023-40271

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.15% 0.32% +0.17%
2 2025-11-21 0.14% 0.15% +0.02%
3 2025-11-18 — 0.14% —

Full EPSS history (8 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2023-40271

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
7.5 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
 3.9 3.6 [email protected]

Weakness enumeration for CVE-2023-40271

Affected software / configurations for CVE-2023-40271

Vendor Product Version Raw CPE
trustedfirmware trusted_firmware-m 1.6.0 cpe:2.3:o:trustedfirmware:trusted_firmware-m:1.6.0:*:*:*:*:*:*:*
trustedfirmware trusted_firmware-m 1.6.1 cpe:2.3:o:trustedfirmware:trusted_firmware-m:1.6.1:*:*:*:*:*:*:*
trustedfirmware trusted_firmware-m 1.7.0 cpe:2.3:o:trustedfirmware:trusted_firmware-m:1.7.0:*:*:*:*:*:*:*
trustedfirmware trusted_firmware-m 1.8.0 cpe:2.3:o:trustedfirmware:trusted_firmware-m:1.8.0:*:*:*:*:*:*:*

References for CVE-2023-40271

cvelogic Threat Intelligence