UBUNTU-CVE-2026-54875 (CVE-2026-54875)

Vulnerability from osv_ubuntu – Published: 2026-09-29 00:00 – Updated: 2026-09-30 21:26 – Source website
VLAI
Details

Issue summary: A non-constant-time optimized implementation of scalar point multiplication is used for SM2 private key operations on ARM64 and RISC-V platforms. Impact summary: An attacker able to measure the time taken by, or to observe the cache-line access pattern of SM2 signing or decryption on an affected platform can learn information about the secret scalar. CWE: CWE-208: Observable Timing Discrepancy Description: On ARM64 and RISC-V processors, the SM2 curve uses an optimized scalar multiplication implementation whose conditional branches and table look ups are chosen according to the bits of the secret scalar. The execution time and the cache-access pattern therefore depend on the long-term private key (during SM2 decryption) or the per-signature nonce (during SM2 signature generation), forming a timing and cache side-channel. FIPS Impact: no SM2 is not a FIPS algorithm and the optimized SM2 implementation is not part of the FIPS module. OpenSSL 4.0, 3.6, 3.5 and 3.4 are vulnerable to this issue on AArch64 and RISC-V. OpenSSL 3.0, 1.1.1 and 1.0.2 are not affected by this issue. OpenSSL 4.0 users should upgrade to OpenSSL 4.0.3. OpenSSL 3.6 users should upgrade to OpenSSL 3.6.5. OpenSSL 3.5 users should upgrade to OpenSSL 3.5.9. OpenSSL 3.4 users should upgrade to OpenSSL 3.4.8. This issue was reported on 2 May 2026 by Abhinav Agarwal. It was independently reported on 6 June 2026 by Feng Xue. The fix was developed by Igor Ustinov. -- cut (non-publishing metadata for internal use) -- Reported by: Abhinav Agarwal, Feng Xue Fixed by: Igor Ustinov

Severity
3.7 (Low)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N
N/A (UNKNOWN)
low
References
To clipboard 

{
  "affected": [
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "libnode72",
            "binary_version": "12.22.9~dfsg-1ubuntu3.6+esm2"
          },
          {
            "binary_name": "nodejs",
            "binary_version": "12.22.9~dfsg-1ubuntu3.6+esm2"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this issue as being low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:Pro:22.04:LTS",
        "name": "nodejs",
        "purl": "pkg:deb/ubuntu/nodejs@12.22.9~dfsg-1ubuntu3.6+esm2?arch=source\u0026distro=esm-apps/jammy"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "12.22.5~dfsg-5ubuntu1",
        "12.22.7~dfsg-2ubuntu1",
        "12.22.7~dfsg-2ubuntu3",
        "12.22.9~dfsg-1ubuntu2",
        "12.22.9~dfsg-1ubuntu3",
        "12.22.9~dfsg-1ubuntu3.1",
        "12.22.9~dfsg-1ubuntu3.2",
        "12.22.9~dfsg-1ubuntu3.3",
        "12.22.9~dfsg-1ubuntu3.4",
        "12.22.9~dfsg-1ubuntu3.5",
        "12.22.9~dfsg-1ubuntu3.6",
        "12.22.9~dfsg-1ubuntu3.6+esm2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "efi-shell-aa64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "efi-shell-loongarch64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "efi-shell-riscv64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "efi-shell-x64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-amdsev",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-generic",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-inteltdx",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "ovmf-legacy",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "qemu-efi-aarch64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "qemu-efi-loongarch64",
            "binary_version": "2025.11-3ubuntu7.2"
          },
          {
            "binary_name": "qemu-efi-riscv64",
            "binary_version": "2025.11-3ubuntu7.2"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this issue as being low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "edk2",
        "purl": "pkg:deb/ubuntu/edk2@2025.11-3ubuntu7.2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2025.02-8ubuntu3",
        "2025.11-3ubuntu6",
        "2025.11-3ubuntu7",
        "2025.11-3ubuntu7.2"
      ]
    },
    {
      "ecosystem_specific": {
        "binaries": [
          {
            "binary_name": "efi-shell-aa64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "efi-shell-loongarch64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "efi-shell-riscv64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "efi-shell-x64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-amdsev-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-generic-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-inteltdx-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "ovmf-legacy-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "qemu-efi-aarch64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "qemu-efi-loongarch64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          },
          {
            "binary_name": "qemu-efi-riscv64-hwe",
            "binary_version": "2025.11-3ubuntu8.2"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this issue as being low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "edk2-hwe",
        "purl": "pkg:deb/ubuntu/edk2-hwe@2025.11-3ubuntu8.2?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "2025.11-3ubuntu6",
        "2025.11-3ubuntu8",
        "2025.11-3ubuntu8.2"
      ]
    },
    {
      "ecosystem_specific": {
        "availability": "No subscription required",
        "binaries": [
          {
            "binary_name": "libssl3t64",
            "binary_version": "3.5.5-1ubuntu3.6"
          },
          {
            "binary_name": "openssl",
            "binary_version": "3.5.5-1ubuntu3.6"
          },
          {
            "binary_name": "openssl-provider-legacy",
            "binary_version": "3.5.5-1ubuntu3.6"
          }
        ],
        "priority_reason": "OpenSSL developers have rated this issue as being low severity"
      },
      "package": {
        "ecosystem": "Ubuntu:26.04:LTS",
        "name": "openssl",
        "purl": "pkg:deb/ubuntu/openssl@3.5.5-1ubuntu3.6?arch=source\u0026distro=resolute"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "3.5.5-1ubuntu3.6"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ],
      "versions": [
        "3.5.3-1ubuntu2",
        "3.5.5-1ubuntu1",
        "3.5.5-1ubuntu3",
        "3.5.5-1ubuntu3.2",
        "3.5.5-1ubuntu3.3",
        "3.5.5-1ubuntu3.4",
        "3.5.5-1ubuntu3.5"
      ]
    }
  ],
  "aliases": [],
  "details": "Issue summary: A non-constant-time optimized implementation of scalar point multiplication is used for SM2 private key operations on ARM64 and RISC-V platforms. Impact summary: An attacker able to measure the time taken by, or to observe the cache-line access pattern of SM2 signing or decryption on an affected platform can learn information about the secret scalar. CWE: CWE-208: Observable Timing Discrepancy Description: On ARM64 and RISC-V processors, the SM2 curve uses an optimized scalar multiplication implementation whose conditional branches and table look ups are chosen according to the bits of the secret scalar. The execution time and the cache-access pattern therefore depend on the long-term private key (during SM2 decryption) or the per-signature nonce (during SM2 signature generation), forming a timing and cache side-channel. FIPS Impact: no SM2 is not a FIPS algorithm and the optimized SM2 implementation is not part of the FIPS module. OpenSSL 4.0, 3.6, 3.5 and 3.4 are vulnerable to this issue on AArch64 and RISC-V. OpenSSL 3.0, 1.1.1 and 1.0.2 are not affected by this issue. OpenSSL 4.0 users should upgrade to OpenSSL 4.0.3. OpenSSL 3.6 users should upgrade to OpenSSL 3.6.5. OpenSSL 3.5 users should upgrade to OpenSSL 3.5.9. OpenSSL 3.4 users should upgrade to OpenSSL 3.4.8. This issue was reported on 2 May 2026 by Abhinav Agarwal. It was independently reported on 6 June 2026 by Feng Xue. The fix was developed by Igor Ustinov. -- cut (non-publishing metadata for internal use) -- Reported by: Abhinav Agarwal, Feng Xue Fixed by: Igor Ustinov",
  "id": "UBUNTU-CVE-2026-54875",
  "modified": "2026-09-30T21:26:48Z",
  "published": "2026-09-29T00:00:00Z",
  "references": [
    {
      "type": "REPORT",
      "url": "https://ubuntu.com/security/CVE-2026-54875"
    },
    {
      "type": "REPORT",
      "url": "https://www.cve.org/CVERecord?id=CVE-2026-54875"
    },
    {
      "type": "REPORT",
      "url": "https://openssl-library.org/news/secadv/20260929.txt"
    },
    {
      "type": "ADVISORY",
      "url": "https://ubuntu.com/security/notices/USN-8847-1"
    }
  ],
  "related": [
    "USN-8847-1"
  ],
  "schema_version": "1.7.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "low",
      "type": "Ubuntu"
    }
  ],
  "upstream": [
    "CVE-2026-54875"
  ]
}



Log in or create an account to share your comment.




Tags
Taxonomy of the tags.





Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.