libgnutls in GnuTLS before 2.8.2 does not properly handle a '\0' character in a domain name in the subject's (1) Common Name (CN) or (2) Subject Alternative Name (SAN) field of an X.509 certificate, which allows man-in-the-middle attackers to spoof arbitrary SSL servers via a crafted certificate issued by a legitimate Certification Authority.
The Network Security Services (NSS) library before 3.12.3, as used in Firefox; GnuTLS before 2.6.4 and 2.7.4; OpenSSL 0.9.8 through 0.9.8k; and other products support MD2 with X.509 certificates, which might allow remote attackers to spoof certificates by using MD2 design flaws to generate a hash collision in less than brute-force time. NOTE: the scope of this issue is currently limited because the amount of computation required is still large.
Mutt 1.5.19, when linked against (1) OpenSSL (mutt_ssl.c) or (2) GnuTLS (mutt_ssl_gnutls.c), allows connections when only one TLS certificate in the chain is accepted instead of verifying the entire chain, which allows remote attackers to spoof trusted servers via a man-in-the-middle attack.
lib/pk-libgcrypt.c in libgnutls in GnuTLS before 2.6.6 does not properly handle invalid DSA signatures, which allows remote attackers to cause a denial of service (application crash) and possibly have unspecified other impact via a malformed DSA key that triggers a (1) free of an uninitialized pointer or (2) double free.
lib/gnutls_pk.c in libgnutls in GnuTLS 2.5.0 through 2.6.5 generates RSA keys stored in DSA structures, instead of the intended DSA keys, which might allow remote attackers to spoof signatures on certificates or have unspecified other impact by leveraging an invalid DSA key.
gnutls-cli in GnuTLS before 2.6.6 does not verify the activation and expiration times of X.509 certificates, which allows remote attackers to successfully present a certificate that is (1) not yet valid or (2) no longer valid, related to lack of time checks in the _gnutls_x509_verify_certificate function in lib/x509/verify.c in libgnutls_x509, as used by (a) Exim, (b) OpenLDAP, and (c) libsoup.
GNU screen 4.0.3 creates the /tmp/screen-exchange temporary file with world-readable permissions, which might allow local users to obtain sensitive session information.
Race condition in GNU screen 4.0.3 allows local users to create or overwrite arbitrary files via a symlink attack on the /tmp/screen-exchange temporary file.
Multiple buffer overflows in the (1) recognize_eps_file function (src/psgen.c) and (2) tilde_subst function (src/util.c) in GNU enscript 1.6.1, and possibly earlier, might allow remote attackers to execute arbitrary code via an epsf escape sequence with a long filename.
The gnu.java.security.util.PRNG class in GNU Classpath 0.97.2 and earlier uses a predictable seed based on the system time, which makes it easier for context-dependent attackers to conduct brute force attacks against cryptographic routines that use this class for randomness, as demonstrated against DSA private keys.