CVE-2026-41989

Libgcrypt: Libgcrypt: Denial of Service and buffer overflow via crafted ECDH ciphertext

Libgcrypt before 1.12.2 sometimes allows a heap-based buffer overflow and denial of service via crafted ECDH ciphertext to gcry_pk_decrypt.

CVSS 3.1 · 6.7 Medium EPSS < 1% KEV · Not listed

Vendors

Gnupg

Products

Libgcrypt

CVE-2021-33560

libgcrypt: mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm

Libgcrypt before 1.8.8 and 1.9.x before 1.9.3 mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm, and the window size is not chosen appropriately. This, for example, affects use of ElGamal in OpenPGP.

CVSS 3.1 · 7.5 High EPSS 2.4% KEV · Not listed

Vendors

Debian Fedoraproject Gnupg and 2 more

Products

Debian Linux Fedora Libgcrypt and 6 more

CVE-2019-12904

Libgcrypt: physical addresses being available to other processes leads to a flush-and-reload side-channel attack

In Libgcrypt 1.8.4, the C implementation of AES is vulnerable to a flush-and-reload side-channel attack because physical addresses are available to other processes. (The C implementation is used on platforms where an assembly-language implementation is unavailable.) NOTE: the vendor's position is that the issue report cannot be validated because there is no description of an attack

CVSS 3.1 · 5.9 Medium EPSS 2.2% KEV · Not listed

Vendors

Gnupg Opensuse

Products

Libgcrypt Leap

CVE-2018-0495

ROHNP: Key Extraction Side Channel in Multiple Crypto Libraries

Libgcrypt before 1.7.10 and 1.8.x before 1.8.3 allows a memory-cache side-channel attack on ECDSA signatures that can be mitigated through the use of blinding during the signing process in the _gcry_ecc_ecdsa_sign function in cipher/ecc-ecdsa.c, aka the Return Of the Hidden Number Problem or ROHNP. To discover an ECDSA key, the attacker needs access to either the local machine or a different virtual machine on the same physical host.

CVSS 3.0 · 4.7 Medium EPSS < 1% KEV · Not listed

Vendors

Canonical Debian Gnupg and 2 more

Products

Ubuntu Linux Debian Linux Libgcrypt and 11 more

CVE-2026-41990

Libgcrypt: Libgcrypt: Denial of Service or data integrity issues from missing bounds check during Dilithium signing.

Libgcrypt before 1.12.2 mishandles Dilithium signing. Writes to a static array lack a bounds check but do not use attacker-controlled data.

CVSS 3.1 · 4 Medium EPSS < 1% KEV · Not listed

Vendors

Gnupg

Products

Libgcrypt

CVE-2017-7526

libgcrypt: Use of left-to-right sliding window method allows full RSA key recovery

libgcrypt before version 1.7.8 is vulnerable to a cache side-channel attack resulting into a complete break of RSA-1024 while using the left-to-right method for computing the sliding-window expansion. The same attack is believed to work on RSA-2048 with moderately more computation. This side-channel requires that attacker can run arbitrary software on the hardware where the private RSA key is used.

CVSS 3.0 · 6.1 Medium EPSS 3.8% KEV · Not listed

Vendors

Canonical Debian Gnupg

Products

Ubuntu Linux Debian Linux Libgcrypt

CVE-2021-40528

libgcrypt: ElGamal implementation allows plaintext recovery

The ElGamal implementation in Libgcrypt before 1.9.4 allows plaintext recovery because, during interaction between two cryptographic libraries, a certain dangerous combination of the prime defined by the receiver's public key, the generator defined by the receiver's public key, and the sender's ephemeral exponents can lead to a cross-configuration attack against OpenPGP.

CVSS 3.1 · 5.9 Medium EPSS 1.4% KEV · Not listed

Vendors

Gnupg Redhat

Products

Libgcrypt Enterprise Linux

CVE-2017-9526

libgcrypt: Possible timing attack on EdDSA session key

In Libgcrypt before 1.7.7, an attacker who learns the EdDSA session key (from side-channel observation during the signing process) can easily recover the long-term secret key. 1.7.7 makes a cipher/ecc-eddsa.c change to store this session key in secure memory, to ensure that constant-time point operations are used in the MPI library.

CVSS 3.0 · 5.9 Medium EPSS 2.3% KEV · Not listed

Vendors

Gnupg

Products

Libgcrypt

CVE-2017-0379

libgcrypt: Missing input validation for X25519 curve

Libgcrypt before 1.8.1 does not properly consider Curve25519 side-channel attacks, which makes it easier for attackers to discover a secret key, related to cipher/ecc.c and mpi/ec.c.

CVSS 3.0 · 7.5 High EPSS 3.5% KEV · Not listed

Vendors

Debian Gnupg

Products

Debian Linux Libgcrypt

CVE-2015-7511

libgcrypt: side-channel attack on ECDH with Weierstrass curves

Libgcrypt before 1.6.5 does not properly perform elliptic-point curve multiplication during decryption, which makes it easier for physically proximate attackers to extract ECDH keys by measuring electromagnetic emanations.

CVSS 3.0 · 2.0 Low EPSS < 1% KEV · Not listed

Vendors

Canonical Debian Gnupg

Products

Ubuntu Linux Debian Linux Libgcrypt

CVE-2014-5270

libgcrypt: ELGAMAL side-channel attack

Libgcrypt before 1.5.4, as used in GnuPG and other products, does not properly perform ciphertext normalization and ciphertext randomization, which makes it easier for physically proximate attackers to conduct key-extraction attacks by leveraging the ability to collect voltage data from exposed metal, a different vector than CVE-2013-4576.

CVSS 2.0 · 2.1 Low EPSS < 1% KEV · Not listed

Vendors

Debian Gnupg

Products

Debian Linux Libgcrypt

CVE-2016-6313

libgcrypt: PRNG output is predictable

The mixing functions in the random number generator in Libgcrypt before 1.5.6, 1.6.x before 1.6.6, and 1.7.x before 1.7.3 and GnuPG before 1.4.21 make it easier for attackers to obtain the values of 160 bits by leveraging knowledge of the previous 4640 bits.

CVSS 3.0 · 5.3 Medium EPSS 3.6% KEV · Not listed

Vendors

Canonical Debian Gnupg and 1 more

Products

Ubuntu Linux Debian Linux Gnupg and 2 more

CVE-2013-4242

GnuPG susceptible to Yarom/Falkner flush+reload cache side-channel attack

GnuPG before 1.4.14, and Libgcrypt before 1.5.3 as used in GnuPG 2.0.x and possibly other products, allows local users to obtain private RSA keys via a cache side-channel attack involving the L3 cache, aka Flush+Reload.

CVSS 2.0 · 1.9 Low EPSS < 1% KEV · Not listed

Vendors

Canonical Debian Gnupg and 2 more

Products

Ubuntu Linux Debian Linux Gnupg and 3 more

CVE-2021-3345

libgcrypt: Heap buffer overflow in the block buffer management code

_gcry_md_block_write in cipher/hash-common.c in Libgcrypt version 1.9.0 has a heap-based buffer overflow when the digest final function sets a large count value. It is recommended to upgrade to 1.9.1 or later.

CVSS 3.1 · 7.8 High EPSS 1.1% KEV · Not listed

Vendors

Gnupg Oracle

Products

Libgcrypt Communications Billing And Revenue Management

CVE-2018-6829

libgcrypt: ElGamal implementation doesn't have semantic security due to incorrectly encoded plaintexts possibly allowing to obtain sensitive information

cipher/elgamal.c in Libgcrypt through 1.8.2, when used to encrypt messages directly, improperly encodes plaintexts, which allows attackers to obtain sensitive information by reading ciphertext data (i.e., it does not have semantic security in face of a ciphertext-only attack). The Decisional Diffie-Hellman (DDH) assumption does not hold for Libgcrypt's ElGamal implementation.

CVSS 3.0 · 7.5 High EPSS 1.8% KEV · Not listed

Vendors

Gnupg

Products

Libgcrypt

CVE-2015-0837

libgcrypt: last-level cache side-channel attack

The mpi_powm function in Libgcrypt before 1.6.3 and GnuPG before 1.4.19 allows attackers to obtain sensitive information by leveraging timing differences when accessing a pre-computed table during modular exponentiation, related to a "Last-Level Cache Side-Channel Attack."

CVSS 3.1 · 5.9 Medium EPSS 2.0% KEV · Not listed

Vendors

Debian Gnupg

Products

Debian Linux Gnupg Libgcrypt

CVE-2014-3591

libgcrypt: use ciphertext blinding for Elgamal decryption (new side-channel attack)

Libgcrypt before 1.6.3 and GnuPG before 1.4.19 does not implement ciphertext blinding for Elgamal decryption, which allows physically proximate attackers to obtain the server's private key by determining factors using crafted ciphertext and the fluctuations in the electromagnetic field during multiplication.

CVSS 3.1 · 4.2 Medium EPSS < 1% KEV · Not listed

Vendors

Debian Gnupg

Products

Debian Linux Gnupg Libgcrypt