Common Weakness Enumeration
CWE-1255
AllowedComparison Logic is Vulnerable to Power Side-Channel Attacks
Abstraction: Variant · Status: Draft
A device's real time power consumption may be monitored during security token evaluation and the information gleaned may be used to determine the value of the reference token.
2 vulnerabilities reference this CWE, most recent first.
CVE-2026-63410 (GCVE-0-2026-63410)
Vulnerability from cvelistv5 – Published: 2026-10-30 22:48 – Updated: 2026-11-02 14:50
VLAI
EPSS
VEX
Title
secp256k1-native: Compiler-reconstructed secret-dependent branch in native scalar multiplication
Summary
secp256k1-native is a native C secp256k1 implementation for Ruby. In affected native builds, native constant-time scalar multiplication through `Point#mul` or `scalar_multiply_ct` can leak timing information about a secret scalar when compiled by a toolchain that reconstructs branchless selection into a branch. The `Montgomery ladder` uses `uint256_select` with an all-zeros or all-ones mask, but affected GCC builds at `-O2` recover the original condition and emit secret-dependent `je` or `jne` jumps whose timing correlates with scalar bits. This defeats the assumption behind the 0.17.0 `jp_add_internal` infinity-branch fix. A consumer must multiply a secret private key or nonce in a context where an attacker can observe timing; repeated measurements can statistically recover scalar bits. The defect is in the compiled binary, so source review or `ctgrind` on a non-reconstructing toolchain may miss it. GCC 14.3.0, 15.1.0, and 15.2.0 reproduced the branch reconstruction, and `extconf.rb` appends `-O2`. Tested GCC versions through 12.4.0 used bitwise operations and GCC 13.3.0 used constant-time `cmov`; the pure-Ruby path is not affected by this flaw and separately makes no constant-time claim. GCC 16 and clang were untested, and point releases, targets, and flag combinations were not exhaustively bisected. `Earlier pre-0.17.0 versions had different constant-time issues rather than this introduced select idiom.` Version 0.18.0 contains the verified fix. The advisory's broad pre-0.18.0 guidance also covers earlier, different constant-time issues; whether this CVE groups those issues or only the select idiom introduced in 0.17.0 remains unresolved.
Severity
5.9 (Medium)
SSVC
Exploitation: poc
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-11-02 14:49 UTC
CWE
Assigner
GitHub_M
CNA
References
5 references
| URL | Tags |
|---|---|
| https://github.com/sgbett/secp256k1-native/securi… | x_refsource_CONFIRM |
| https://github.com/sgbett/secp256k1-native/pull/32 | x_refsource_MISC |
| https://github.com/sgbett/secp256k1-native/commit… | x_refsource_MISC |
| https://github.com/sgbett/secp256k1-native/blob/m… | x_refsource_MISC |
| https://github.com/sgbett/secp256k1-native/releas… | x_refsource_MISC |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| sgbett | secp256k1-native |
Affected:
>= 0.17.0, < 0.18.0
|
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CVE-2025-3301 (GCVE-0-2025-3301)
Vulnerability from cvelistv5 – Published: 2025-04-29 13:47 – Updated: 2025-04-29 14:02
VLAI
EPSS
VEX
Title
DPA Countermeasures Unavailable for Certain Cryptographic Operations on Series 2 Devices
Summary
DPA countermeasures are unavailable for ECDH key agreement and EdDSA signing operations on Curve25519 and Curve448 on all Series 2 modules and SoCs due to a lack of hardware and software support. A successful DPA attack may result in exposure of confidential information. The best practice is to use the impacted crypto curves and operations with ephemeral keys to reduce the number of DPA traces that can be collected.
Severity
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-04-29 14:01 UTC
CWE
- CWE-1255 - Comparison Logic is Vulnerable to Power Side-Channel Attacks
Assigner
Silabs
CNA
References
1 reference
| URL | Tags |
|---|---|
| https://community.silabs.com/068Vm00000O8qbY | vendor-advisorypermissions-required |
Impacted products
1 product
| Vendor | Product | Version | |
|---|---|---|---|
| silabs.com | Series 2 SoCs and associated modules |
Affected:
0 , ≤ all released hardware revisions
(custom)
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Mitigation
Architecture and Design
The design phase must consider each check of a security token against a standard and the amount of power consumed during the check of a good token versus a bad token. The alternative is an all at once check where a retry counter is incremented PRIOR to the check.
Mitigation
Architecture and Design
Another potential mitigation is to parallelize shifting of secret data (see example 2 below). Note that the wider the bus the more effective the result.
Mitigation
Architecture and Design
An additional potential mitigation is to add random data to each crypto operation then subtract it out afterwards. This is highly effective but costly in performance, area, and power consumption. It also requires a random number generator.
Mitigation
Implementation
If the architecture is unable to prevent the attack, using filtering components may reduce the ability to implement an attack, however, consideration must be given to the physical removal of the filter elements.
Mitigation
Integration
During integration, avoid use of a single secret for an extended period (e.g. frequent key updates). This limits the amount of data compromised but at the cost of complexity of use.
CAPEC-189: Black Box Reverse Engineering
An adversary discovers the structure, function, and composition of a type of computer software through black box analysis techniques. 'Black Box' methods involve interacting with the software indirectly, in the absence of direct access to the executable object. Such analysis typically involves interacting with the software at the boundaries of where the software interfaces with a larger execution environment, such as input-output vectors, libraries, or APIs. Black Box Reverse Engineering also refers to gathering physical side effects of a hardware device, such as electromagnetic radiation or sounds.