-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 OpenSSL Security Advisory [15th January 2024] ============================================= Excessive time spent checking invalid RSA public keys (CVE-2023-6237) ===================================================================== Severity: Low Issue summary: Checking excessively long invalid RSA public keys may take a long time. Impact summary: Applications that use the function EVP_PKEY_public_check() to check RSA public keys may experience long delays. Where the key that is being checked has been obtained from an untrusted source this may lead to a Denial of Service. When function EVP_PKEY_public_check() is called on RSA public keys, a computation is done to confirm that the RSA modulus, n, is composite. For valid RSA keys, n is a product of two or more large primes and this computation completes quickly. However, if n is an overly large prime, then this computation would take a long time. An application that calls EVP_PKEY_public_check() and supplies an RSA key obtained from an untrusted source could be vulnerable to a Denial of Service attack. The function EVP_PKEY_public_check() is not called from other OpenSSL functions however it is called from the OpenSSL pkey command line application. For that reason that application is also vulnerable if used with the "-pubin" and "-check" options on untrusted data. The OpenSSL SSL/TLS implementation is not affected by this issue. The OpenSSL 3.0 and 3.1 FIPS providers are affected by this issue. OpenSSL versions 3.0.0 to 3.0.12, 3.1.0 to 3.1.4 and 3.2.0 are vulnerable to this issue. OpenSSL versions 1.1.1 and 1.0.2 are not affected by this issue. Due to the low severity of this issue we are not issuing new releases of OpenSSL at this time. The fix will be included in the next releases when they become available. The fix is also available in commit 0b0f7abf (for 3.2), commit a830f551 (for 3.1) and commit 18c02492 (for 3.0) in the OpenSSL git repository. This issue was reported on 2nd November 2023 by OSS-Fuzz. The fix was developed by Tomas Mraz. General Advisory Notes ====================== URL for this Security Advisory: https://www.openssl.org/news/secadv/20240115.txt Note: the online version of the advisory may be updated with additional details over time. For details of OpenSSL severity classifications please see: https://www.openssl.org/policies/secpolicy.html -----BEGIN PGP SIGNATURE----- iQIzBAEBCAAdFiEE3HAyZir4heL0fyQ/UnRmohynnm0FAmWlJXsACgkQUnRmohyn nm067Q//X41VgBUcS9YWimbkD7Pj1nWIhgOUOTaXcBTkroNOjgiJOBuqnOKJorj6 N0KuAA9d+Jq3xVFbwFNiZZDl2O3Az8nmW9Yg63xyoZNXeB/80ZhUCcxX+mrnKeSt XUJ8y5bSLuFrDsSp1Ew+xnfAo8DXn3DhRwHKi9Ww0kwdAN5+j84mtnGC3MfTAdLN 2WAnRY/AJGL4dACB2HEMz0zv6wU8QtV0hQUOwsDus8zw+6jkdOWpnadmqzA884MS qJsKFLUN+ca64E0VsjLzHipJK464Qdyp1QIm7QG6hZtb3IDjb6oK4zo1M7bGvR+O Wt6NKUMUovVYX6h3/e+Qpki0RS2rdxqbjTcXms2ijq/70iNrhP5p7nMfQWUkQM9G QDwV0E+5OvOh1t1eHnn7MjGhUGEhTGeGXJ/oACt96i47lzYtobovi2y+B0fRhsuf L8CPrArteBsFcPDyS/1Z/88HmOtDa9QhCawvAv9j8pwZgBxR0BV9fqsG4i+Mshdl h88J/Xbd5+Gzp1Zt8F2eQlYk8xL3aPrIOmuYym3wbiXXXSRI894jyae7+AV2WItK 1FBVXw4wlh+ZPOaAOMEirxYMZ5+6c2wYyd9XEHlw+J6vjU+/CtM0Z2SYg/b56dkJ ko/9Dor3UF6JjWdfOZqZXEOk8Rk20VHF9lDllJk8Xu2GAO5Wuug= =UUwr -----END PGP SIGNATURE-----
