Botan before 1.10.13 and 1.11.x before 1.11.29 do not use a constant-time algorithm to perform a modular inverse on the signature nonce k, which might allow remote attackers to obtain ECDSA secret keys via a timing side-channel attack.

Integer overflow in the PointGFp constructor in Botan before 1.10.11 and 1.11.x before 1.11.27 allows remote attackers to overwrite memory and possibly execute arbitrary code via a crafted ECC point, which triggers a heap-based buffer overflow.

Heap-based buffer overflow in the P-521 reduction function in Botan 1.11.x before 1.11.27 allows remote attackers to cause a denial of service (memory overwrite and crash) or execute arbitrary code via unspecified vectors.