CVE-2026-54872
LowCVSS 3.7Exploitation Probability (EPSS)
Low risk17th percentile - higher than 17% of all known CVEs
Summary
The generic elliptic-curve scalar multiplication used for ECDSA and SM2 signature operations with curves lacking a dedicated implementation leaks information about the secret nonce through timing. An attacker measuring signing times may learn the nonce, which over many signatures can lead to private key recovery.
Risk Assessment
Disclosure of the secret nonce may allow an attacker to recover the private key, leading to complete compromise of digital signatures and communication confidentiality.
Recommendation
Use curves with dedicated constant-time implementations (e.g., NIST P-256, P-384, P-521) or update the cryptographic library to a patched version.
Other vulnerabilities in OpenSSL
See all- CVE-2016-8610High
A denial of service flaw was found in OpenSSL 0.9.8, 1.0.1, 1.0.2 through 1.0.2h, and 1.1.0 in the way the TLS/SSL protocol defined processing of ALERT packets during a connection handshake. A remote attacker could use this flaw to make a TLS/SSL server consume an excessive amount of CPU and fail to accept connections from other clients.
- CVE-2017-3731High
CVE-2017-3731 affects SSL/TLS servers and clients running on 32-bit hosts that may crash due to an out-of-bounds read caused by a truncated packet. For OpenSSL 1.1.0, the crash can be triggered using the CHACHA20/POLY1305 cipher, and for OpenSSL 1.0.2 using RC4-MD5.
- CVE-2017-3730High
In OpenSSL 1.1.0 before 1.1.0d, a malicious server can supply bad parameters for a DHE or ECDHE key exchange, leading to the client attempting to dereference a NULL pointer, resulting in a client crash.
- CVE-2016-7054High
In OpenSSL 1.1.0 before 1.1.0c, TLS connections using *-CHACHA20-POLY1305 ciphersuites are susceptible to a DoS attack by corrupting larger payloads. This can result in an OpenSSL crash.
- CVE-2016-7052High
OpenSSL 1.0.2i has a vulnerability that allows remote attackers to cause application crashes by triggering a CRL operation, leading to a NULL pointer dereference.
- CVE-2016-6305High
The ssl3_read_bytes function in OpenSSL 1.1.0 before version 1.1.0a allows remote attackers to cause a denial of service (infinite loop) by triggering a zero-length record in an SSL_peek call.
- CVE-2016-6304High
Multiple memory leaks in t1_lib.c in OpenSSL before 1.0.1u, 1.0.2 before 1.0.2i, and 1.1.0 before 1.1.0a allow remote attackers to cause a denial of service (memory consumption) via large OCSP Status Request extensions.
- CVE-2016-6302High
The tls_decrypt_ticket function in OpenSSL before 1.1.0 does not consider the HMAC size during validation of the ticket length, allowing remote attackers to cause a denial of service via a ticket that is too short.
- CVE-2016-2179High
The DTLS implementation in OpenSSL before 1.1.0 does not properly restrict the lifetime of queue entries associated with unused out-of-order messages. This allows remote attackers to cause a denial of service (memory consumption) by maintaining many crafted DTLS sessions simultaneously.
- CVE-2016-2176High
The X509_NAME_oneline function in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to obtain sensitive information from process stack memory or cause a denial of service (buffer over-read) via crafted EBCDIC ASN.1 data.
Original NVD description (English source)
Issue summary: The generic elliptic-curve scalar multiplication used for ECDSA and SM2 signature operations with curves that do not have a dedicated implementation leaks information about the secret nonce through timing. Impact summary: An attacker able to measure signing times may learn information about the per-signature secret nonce, which over many signatures can, via a lattice / Hidden Number Problem attack, lead to recovery of the private key. CWE: CWE-208: Observable Timing Discrepancy Description: The generic elliptic-curve scalar multiplication used for curves that do not have a dedicated constant-time implementation pads the secret scalar with non-constant-time BIGNUM operations, so the time taken depends on the value of the secret scalar derived from the ECDSA and SM2 nonce. The leak is very small; observing it requires a large number of measurements. The effect is largest for curves whose group order lies on a machine-word boundary, such as brainpoolP384r1. Applications using ECDSA signing over the Brainpool and other generic prime curves, and SM2 signing on platforms that use the generic implementation, are vulnerable to this issue. The NIST curves P-256, P-384 and P-521 use dedicated constant-time implementations and are not affected. FIPS Impact: no The FIPS modules are not affected: the approved NIST curves used in the FIPS provider have dedicated constant-time implementations and do not use the affected code path.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS