CVE-2021-40528 – libgcrypt: ElGamal implementation allows plaintext recovery
https://notcve.org/view.php?id=CVE-2021-40528
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. Una implementación de ElGamal en Libgcrypt versiones anteriores a 1.9.4, permite una recuperación de texto plano porque, durante la interacción entre dos bibliotecas criptográficas, una determinada combinación peligrosa del primo definido por la clave pública del receptor, el generador definido por la clave pública del receptor y los exponentes efímeros del emisor puede conllevar a un ataque de configuración cruzada contra OpenPGP. A flaw was found in libgcrypt's ElGamal implementation, where it allows plain text recovery. During the interaction between two cryptographic libraries, a certain 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. The highest threat from this vulnerability is to confidentiality. • https://eprint.iacr.org/2021/923 https://git.gnupg.org/cgi-bin/gitweb.cgi?p=libgcrypt.git%3Ba=commit%3Bh=3462280f2e23e16adf3ed5176e0f2413d8861320 https://ibm.github.io/system-security-research-updates/2021/07/20/insecurity-elgamal-pt1 https://ibm.github.io/system-security-research-updates/2021/09/06/insecurity-elgamal-pt2 https://security.gentoo.org/glsa/202210-13 https://access.redhat.com/security/cve/CVE-2021-40528 https://bugzilla.redhat.com/show_bug.cgi?id=2002816 • CWE-327: Use of a Broken or Risky Cryptographic Algorithm •
CVE-2021-33560 – libgcrypt: mishandles ElGamal encryption because it lacks exponent blinding to address a side-channel attack against mpi_powm
https://notcve.org/view.php?id=CVE-2021-33560
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. Libgcrypt versiones anteriores a 1.8.8 y versiones 1.9.x anteriores a 1.9.3, maneja inapropiadamente el cifrado de ElGamal porque carece de cegado de exponentes para hacer frente a un ataque de canal lateral contra la función mpi_powm, y el tamaño de la ventana no se elige apropiadamente. Esto, por ejemplo, afecta el uso de ElGamal en OpenPGP. A side-channel attack flaw was found in the way libgcrypt implemented Elgamal encryption. • https://github.com/IBM/PGP-client-checker-CVE-2021-33560 https://dev.gnupg.org/T5305 https://dev.gnupg.org/T5328 https://dev.gnupg.org/T5466 https://dev.gnupg.org/rCe8b7f10be275bcedb5fc05ed4837a89bfd605c61 https://lists.debian.org/debian-lts-announce/2021/06/msg00021.html https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/BKKTOIGFW2SGN3DO2UHHVZ7MJSYN4AAB https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/R7OAPCUGPF3VLA7QAJUQSL255D4ITVTL • CWE-203: Observable Discrepancy CWE-327: Use of a Broken or Risky Cryptographic Algorithm •
CVE-2019-12904
https://notcve.org/view.php?id=CVE-2019-12904
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 ** EN DISPUTA ** En Libgcrypt versión 1.8.4, la implementación en C de AES es vulnerable a un ataque de canal lateral de descarga y recarga porque las direcciones físicas están disponibles para otros procesos. (La implementación en C se usa en plataformas donde una implementación en lenguaje ensamblador no está disponible). NOTA: la posición del vendedor es que el informe de emisión no puede ser validado porque no hay descripción de un ataque • http://lists.opensuse.org/opensuse-security-announce/2019-07/msg00049.html https://dev.gnupg.org/T4541 https://github.com/gpg/libgcrypt/commit/a4c561aab1014c3630bc88faf6f5246fee16b020 https://github.com/gpg/libgcrypt/commit/daedbbb5541cd8ecda1459d3b843ea4d92788762 https://lists.apache.org/thread.html/rf9fa47ab66495c78bb4120b0754dd9531ca2ff0430f6685ac9b07772%40%3Cdev.mina.apache.org%3E • CWE-668: Exposure of Resource to Wrong Sphere •