liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography algorithms. Multiple secret-dependent branches have been identified in the reference implementation of the HQC key encapsulation mechanism when it is compiled with Clang for optimization levels above -O0 (-O1, -O2, etc). A proof-of-concept local attack exploits this secret-dependent information to recover the entire secret key. This vulnerability is fixed in 0.14.0.

The remote openSUSE 16 host has packages installed that are affected by multiple vulnerabilities as referenced in the openSUSE-SU-2026:21634-1 advisory.

    Changes in liboqs:

    Updated to 0.16.0:

      Deprecation notice:

      - SPHINCS+ was removed in 0.16.0.

      Security issues:

      - Fixed uninitialized `encaps_derand` pointer dereference
      - CVE-2026-46344, CVE-2026-44518: Fixed out-of-bounds read in XMSS/XMSS^MT signature verification         (bsc#1267007 bsc#1267001)
      - Fixed Integer underflow in CROSS `crypto_sign_open()`
      - Fixed incorrect array size when calling `secure_clean`
      - Implemented optimization barrier `OQS_MEM_BLACK_BOX` and applied to `ct_select` in FrodoKEM

      Significant change:

      FrodoKEM algorithm change:

      * Existing FrodoKEM in 0.15.0 was renamed to ephemeral         FrodoKEM (`KEM_efrodokem_<640|976|1344>_<aes|shake>`), and         the salted variant of FrodoKEM was added under the prior names         (`KEM_frodokem_<640|976|1344>_<aes|shake>`).

        Ephemeral FrodoKEM is recommended for applications         where each keypair will encapsulate only a small number         of shared secrets and ciphertexts. Standard (salted)         FrodoKEM is recommended for applications where each keypair         is expected to encapsulate large number of ciphertexts. Please consult         [upstream](https://github.com/microsoft/PQCrypto-LWEKE/#frodokem-learning-with-errors-key-     encapsulation)         for more details.

      * mldsa-native integration:

        mldsa-native is a secure, fast, and portable C90 implementation of the         ML-DSA post-quantum signature standard. It also includes optimized         builds for x86_64 and aarch64. It is now the default implementation         behind `SIG_ml_dsa_<44|65|87>`.

      * Updated HQC implementation:

        The HQC implementations in liboqs were updated to 20250822         spec. Its upstream switched from PQClean to the [official         repo](https://gitlab.com/pqc-hqc/hqc). `KEM_hqc_<1|3|5>` is now enabled         by default.

      * MQOM integration and memory-optimized build flag:

        MQOM is a third-round candidate in NIST's Additional Digital         Signatures for the PQC Standardization Process. Portable,         x86_64-optimized, and memory-optimized implementations were         integrate?into liboqs under `OQS_ENABLE_SIG_MQOM`.


      * OpenSSH implementation of NTRU Prime:

        A public-domain OpenSSH implementation of NTRUPrime761         replaced the PQClean implementation as the default backend for         `KEM_ntruprime_sntrup761`.

      Bug fixes:

      - Fixed incremental absorption bug in AVX512VL SHA3-512 [#2442](https://github.com/open-quantum-     safe/liboqs/pull/2442)
      - Implemented fallback for when `EVP_DigestSqueeze` is unavailable [#2433](https://github.com/open-     quantum-safe/liboqs/pull/2433)
      - Added API for detecting stateful signature support at runtime [#2434](https://github.com/open-quantum-     safe/liboqs/pull/2434)
      - Fixed missing initialization and indexing bug in LMS [#2416](https://github.com/open-quantum-     safe/liboqs/pull/2416)
      - Fixed erroneous MAYO_OK despite failed sample_solution() attempts in MAYO     [#2403](https://github.com/open-quantum-safe/liboqs/pull/2403)
      - Limited pytest parallelism to prevent memory exhaustion in constrained environment     [#2397](https://github.com/open-quantum-safe/liboqs/pull/2397)
      - Fixed cuPQC ML-KEM derand symbol names and `#if/#elif` chains [#2396](https://github.com/open-quantum-     safe/liboqs/pull/2396)
      - Tightened Windows compiler detection [#2394](https://github.com/open-quantum-safe/liboqs/pull/2394)
      - Fixed mismatched macros in LMS [#2379](https://github.com/open-quantum-safe/liboqs/pull/2379)
      - Made fuzzers tolerant to disabled algorithms [#2359](https://github.com/open-quantum-     safe/liboqs/pull/2359)
      - Removed inlined exponentiation in CROSS-RSDPG-1 [#2357](https://github.com/open-quantum-     safe/liboqs/pull/2357)
      - Fixed incorrect arg register update in AVX512 Keccak [#2330](https://github.com/open-quantum-     safe/liboqs/pull/2330)

    - Update to 0.15.0:
      * Significant changes:
        - Integrated SLH-DSA implementation from pq-code-package/slhdsa-c
        - SLH-DSA ACVP tests (#2237)
        - Integrate SLH-DSA-C Library (#2175)
        - Added NTRU back (#2176)
        - Removed all Dilithium implementations (#2275)
        - Replaced SPHINCS+ with SLH-DSA for CMake build option           OQS_ALGS_ENABLED=STD (#2290)
        - Updated CROSS to version 2.2 (#2247)
        - Included DeriveEncapsulation functionality (#2221)
        - Integrated ML-KEM implementation from ICICLE-PQC (#2216)
      * Bug fixes:
        - Fixed erroneously disabled LMS variants with build flag           OQS_ENABLE_SIG_STFL_LMS (#2310)
        - Fixed incorrect import in OV-III-pkc_skc (#2299)
        - Fixed incorrect actual signature length in signature full-cycle           speed test (#2293)
        - Fixed ICICLE ML-KEM integration (#2288)
        - Disabled strict aliasing on SPHINCS+-SHAKE (#2264)
        - Fixed uninitialized length_encaps_seed for NTRU implementations (#2266)
        - Changed 64 bit add to 32 bit add to wrap on 32 bit counter for           AES-CTR AES-NI implementation (#2252)
        - Improved random number generator security (#2225)
        - Added Classic McEliece sanitization patch (#2218)
      * Miscellaneous:
        - Deprecated noregress scripts (#2295)
        - Updated no-pass explanation for constant-time testing (#2294)
        - Re-enabled all ACVP tests (#2283)
        - Updated license info for ML-KEM (#2250)
        - Added Poutine SASL (#2213)
        - Updated ACVP to 1.1.0.40 (#2172)
        - Switched to dev mode for 0.14.1 (#2199)
      * Deprecation notice: liboqs 0.15.0 is the last version to officially         support SPHINCS+. SPHINCS+ will be removed in the 0.16.0 release and         replaced by SLH-DSA. liboqs 0.15.0 also removes support for Dilithium.

    Updated to 0.14.0:

      * Key encapsulation mechanisms:
        - HQC: Disabled compiler optimizations to avoid secret-dependent branching in certain configurations.
    HQC remains disabled by default.
        - ML-KEM: Updated the default ML-KEM implementation to [PQCP's mlkem-native     v1.0.0](https://github.com/pq-code-package/mlkem-native/releases/tag/v1.0.0).
      * Digital signature schemes:
        - New API: added an API function to check if a signature scheme supports signing with a context     string.
        - SNOVA: added [SNOVA](https://snova.pqclab.org/) from NIST Additional Signature Schemes Round 2.


Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The remote SUSE Linux SLED15 / SLED_SAP15 / SLES15 / SLES_SAP15 host has packages installed that are affected by multiple vulnerabilities as referenced in the SUSE-SU-2026:3420-1 advisory.

    - disable KEM_HQC and SIG_MQOM and KEM_NTRUPRIME on s390x for now, testsuite shows them not working.

    Updated to 0.16.0:

      Deprecation notice:

      - SPHINCS+ was removed in 0.16.0.

      Security issues:

      - Fixed uninitialized `encaps_derand` pointer dereference
      - CVE-2026-46344, CVE-2026-44518: Fixed out-of-bounds read in XMSS/XMSS^MT signature verification         (bsc#1267007 bsc#1267001)
      - Fixed Integer underflow in CROSS `crypto_sign_open()`
      - Fixed incorrect array size when calling `secure_clean`
      - Implemented optimization barrier `OQS_MEM_BLACK_BOX` and applied to `ct_select` in FrodoKEM

      Significant change:

      FrodoKEM algorithm change:

      * Existing FrodoKEM in 0.15.0 was renamed to ephemeral         FrodoKEM (`KEM_efrodokem_<640|976|1344>_<aes|shake>`), and         the salted variant of FrodoKEM was added under the prior names         (`KEM_frodokem_<640|976|1344>_<aes|shake>`).
        Ephemeral FrodoKEM is recommended for applications         where each keypair will encapsulate only a small number         of shared secrets and ciphertexts. Standard (salted)         FrodoKEM is recommended for applications where each keypair         is expected to encapsulate large number of ciphertexts. Please consult         [upstream](https://github.com/microsoft/PQCrypto-LWEKE/#frodokem-learning-with-errors-key-     encapsulation)         for more details.
      * mldsa-native integration:
        mldsa-native is a secure, fast, and portable C90 implementation of the         ML-DSA post-quantum signature standard. It also includes optimized         builds for x86_64 and aarch64. It is now the default implementation         behind `SIG_ml_dsa_<44|65|87>`.
      * Updated HQC implementation:
        The HQC implementations in liboqs were updated to 20250822         spec. Its upstream switched from PQClean to the [official         repo](https://gitlab.com/pqc-hqc/hqc). `KEM_hqc_<1|3|5>` is now enabled         by default.
      * MQOM integration and memory-optimized build flag:
        MQOM is a third-round candidate in NIST's Additional Digital         Signatures for the PQC Standardization Process. Portable,         x86_64-optimized, and memory-optimized implementations were         integrate?into liboqs under `OQS_ENABLE_SIG_MQOM`.
      * OpenSSH implementation of NTRU Prime:
        A public-domain OpenSSH implementation of NTRUPrime761         replaced the PQClean implementation as the default backend for         `KEM_ntruprime_sntrup761`.

      Bug fixes:

      - Fixed incremental absorption bug in AVX512VL SHA3-512 [#2442](https://github.com/open-quantum-     safe/liboqs/pull/2442)
      - Implemented fallback for when `EVP_DigestSqueeze` is unavailable [#2433](https://github.com/open-     quantum-safe/liboqs/pull/2433)
      - Added API for detecting stateful signature support at runtime [#2434](https://github.com/open-quantum-     safe/liboqs/pull/2434)
      - Fixed missing initialization and indexing bug in LMS [#2416](https://github.com/open-quantum-     safe/liboqs/pull/2416)
      - Fixed erroneous MAYO_OK despite failed sample_solution() attempts in MAYO     [#2403](https://github.com/open-quantum-safe/liboqs/pull/2403)
      - Limited pytest parallelism to prevent memory exhaustion in constrained environment     [#2397](https://github.com/open-quantum-safe/liboqs/pull/2397)
      - Fixed cuPQC ML-KEM derand symbol names and `#if/#elif` chains [#2396](https://github.com/open-quantum-     safe/liboqs/pull/2396)
      - Tightened Windows compiler detection [#2394](https://github.com/open-quantum-safe/liboqs/pull/2394)
      - Fixed mismatched macros in LMS [#2379](https://github.com/open-quantum-safe/liboqs/pull/2379)
      - Made fuzzers tolerant to disabled algorithms [#2359](https://github.com/open-quantum-     safe/liboqs/pull/2359)
      - Removed inlined exponentiation in CROSS-RSDPG-1 [#2357](https://github.com/open-quantum-     safe/liboqs/pull/2357)
      - Fixed incorrect arg register update in AVX512 Keccak [#2330](https://github.com/open-quantum-     safe/liboqs/pull/2330)

    Update to 0.15.0:

      * Significant changes:

        - Integrated SLH-DSA implementation from pq-code-package/slhdsa-c
        - SLH-DSA ACVP tests (#2237)
        - Integrate SLH-DSA-C Library (#2175)
        - Added NTRU back (#2176)
        - Removed all Dilithium implementations (#2275)
        - Replaced SPHINCS+ with SLH-DSA for CMake build option           OQS_ALGS_ENABLED=STD (#2290)
        - Updated CROSS to version 2.2 (#2247)
        - Included DeriveEncapsulation functionality (#2221)
        - Integrated ML-KEM implementation from ICICLE-PQC (#2216)

      * Bug fixes:

        - Fixed erroneously disabled LMS variants with build flag           OQS_ENABLE_SIG_STFL_LMS (#2310)
        - Fixed incorrect import in OV-III-pkc_skc (#2299)
        - Fixed incorrect actual signature length in signature full-cycle           speed test (#2293)
        - Fixed ICICLE ML-KEM integration (#2288)
        - Disabled strict aliasing on SPHINCS+-SHAKE (#2264)
        - Fixed uninitialized length_encaps_seed for NTRU implementations (#2266)
        - Changed 64 bit add to 32 bit add to wrap on 32 bit counter for           AES-CTR AES-NI implementation (#2252)
        - Improved random number generator security (#2225)
        - Added Classic McEliece sanitization patch (#2218)

      * Miscellaneous:

        - Deprecated noregress scripts (#2295)
        - Updated no-pass explanation for constant-time testing (#2294)
        - Re-enabled all ACVP tests (#2283)
        - Updated license info for ML-KEM (#2250)
        - Added Poutine SASL (#2213)
        - Updated ACVP to 1.1.0.40 (#2172)
        - Switched to dev mode for 0.14.1 (#2199)

      * Deprecation notice: liboqs 0.15.0 is the last version to officially         support SPHINCS+. SPHINCS+ will be removed in the 0.16.0 release and         replaced by SLH-DSA. liboqs 0.15.0 also removes support for Dilithium.

    Updated to 0.14.0:

      * Key encapsulation mechanisms:

        - HQC: Disabled compiler optimizations to avoid secret-dependent branching in certain configurations.
    HQC remains disabled by default.
        - ML-KEM: Updated the default ML-KEM implementation to [PQCP's mlkem-native     v1.0.0](https://github.com/pq-code-package/mlkem-native/releases/tag/v1.0.0).

      * Digital signature schemes:

        - New API: added an API function to check if a signature scheme supports signing with a context     string.
        - SNOVA: added [SNOVA](https://snova.pqclab.org/) from NIST Additional Signature Schemes Round 2.


Tenable has extracted the preceding description block directly from the SUSE security advisory.

Note that Nessus has not tested for these issues but has instead relied only on the application's self-reported version number.

The Linux/Unix host has one or more packages installed that are impacted by a vulnerability without a vendor supplied patch available.

  - liboqs is a C-language cryptographic library that provides implementations of post-quantum cryptography     algorithms. Multiple secret-dependent branches have been identified in the reference implementation of the     HQC key encapsulation mechanism when it is compiled with Clang for optimization levels above -O0 (-O1,
    -O2, etc). A proof-of-concept local attack exploits this secret-dependent information to recover the     entire secret key. This vulnerability is fixed in 0.14.0. (CVE-2025-52473)

Note that Nessus relies on the presence of the package as reported by the vendor.

The version of FreeBSD installed on the remote host is prior to tested version. It is, therefore, affected by a vulnerability as referenced in the aeac223e-60e1-11f0-8baa-8447094a420f advisory.

    The OpenQuantumSafe project reports:
    Secret-dependent branching in HQC reference implementation when compiled with Clang 17-20 for     optimizations above -O0

Tenable has extracted the preceding description block directly from the FreeBSD security advisory.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.

ID	Name	Product	Family	Type	Severity
341166	openSUSE 16 Security Update : liboqs (openSUSE-SU-2026:21634-1)	Nessus	SuSE Local Security Checks	Local	medium
331425	SUSE SLED15 / SLES15 Security Update : liboqs, oqs-provider (SUSE-SU-2026:3420-1)	Nessus	SuSE Local Security Checks	Local	medium
260223	Linux Distros Unpatched Vulnerability : CVE-2025-52473	Nessus	Misc.	Local	medium
242079	FreeBSD : liboqs -- Secret-dependent branching in HQC (aeac223e-60e1-11f0-8baa-8447094a420f)	Nessus	FreeBSD Local Security Checks	Local	medium

Detections

Analytics

CVE-2025-52473

medium

Tenable Plugins

medium

medium

medium

medium