TLS vulnerabilities

SSH, as implemented in OpenSSH before 4.0 and possibly other implementations, stores hostnames, IP addresses, and keys in plaintext in the known_hosts file, which makes it easier for an attacker that has compromised an SSH user's account to generate a list of additional targets that are more likely to have the same password or key.

The design of Advanced Encryption Standard (AES), aka Rijndael, allows remote attackers to recover AES keys via timing attacks on S-box lookups, which are difficult to perform in constant time in AES implementations.

Multiple stack-based buffer overflows in libcURL and cURL 7.12.1, and possibly other versions, allow remote malicious web servers to execute arbitrary code via base64 encoded replies that exceed the intended buffer lengths when decoded, which is not properly handled by (1) the Curl_input_ntlm function in http_ntlm.c during NTLM authentication or (2) the Curl_krb_kauth and krb4_auth functions in krb4.c during Kerberos authentication.

The der_chop script in the openssl package in Trustix Secure Linux 1.5 through 2.1 and other operating systems allows local users to overwrite files via a symlink attack on temporary files.

sshd in OpenSSH 3.5p1, when PermitRootLogin is disabled, immediately closes the TCP connection after a root login attempt with the correct password, but leaves the connection open after an attempt with an incorrect password, which makes it easier for remote attackers to guess the password by observing the connection state, a different vulnerability than CVE-2003-0190. NOTE: it could be argued that in most environments, this does not cross privilege boundaries without requiring leverage of a separate vulnerability.

sshd.c in OpenSSH 3.6.1p2 and 3.7.1p2 and possibly other versions, when using privilege separation, does not properly signal the non-privileged process when a session has been terminated after exceeding the LoginGraceTime setting, which leaves the connection open and allows remote attackers to cause a denial of service (connection consumption).

The SSL/TLS handshaking code in OpenSSL 0.9.7a, 0.9.7b, and 0.9.7c, when using Kerberos ciphersuites, does not properly check the length of Kerberos tickets during a handshake, which allows remote attackers to cause a denial of service (crash) via a crafted SSL/TLS handshake that causes an out-of-bounds read.

OpenSSL 0.9.6 before 0.9.6d does not properly handle unknown message types, which allows remote attackers to cause a denial of service (infinite loop), as demonstrated using the Codenomicon TLS Test Tool.

The do_change_cipher_spec function in OpenSSL 0.9.6c to 0.9.6k, and 0.9.7a to 0.9.7c, allows remote attackers to cause a denial of service (crash) via a crafted SSL/TLS handshake that triggers a null dereference.

The default configuration for OpenSSH enables AllowTcpForwarding, which could allow remote authenticated users to perform a port bounce, when configured with an anonymous access program such as AnonCVS.

Directory traversal vulnerability in scp for OpenSSH before 3.4p1 allows remote malicious servers to overwrite arbitrary files. NOTE: this may be a rediscovery of CVE-2000-0992.

sshd in OpenSSH 3.6.1p2 and earlier, when PermitRootLogin is disabled and using PAM keyboard-interactive authentication, does not insert a delay after a root login attempt with the correct password, which makes it easier for remote attackers to use timing differences to determine if the password step of a multi-step authentication is successful, a different vulnerability than CVE-2003-0190.

OpenSSL 0.9.6k allows remote attackers to cause a denial of service (crash via large recursion) via malformed ASN.1 sequences.

The PAM conversation function in OpenSSH 3.7.1 and 3.7.1p1 interprets an array of structures as an array of pointers, which allows attackers to modify the stack and possibly gain privileges.

The SSH1 PAM challenge response authentication in OpenSSH 3.7.1 and 3.7.1p1, when Privilege Separation is disabled, does not check the result of the authentication attempt, which can allow remote attackers to gain privileges.

Double free vulnerability in OpenSSL 0.9.7 allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via an SSL client certificate with a certain invalid ASN.1 encoding.

OpenSSL 0.9.6 and 0.9.7 does not properly track the number of characters in certain ASN.1 inputs, which allows remote attackers to cause a denial of service (crash) via an SSL client certificate that causes OpenSSL to read past the end of a buffer when the long form is used.

Integer overflow in OpenSSL 0.9.6 and 0.9.7 allows remote attackers to cause a denial of service (crash) via an SSL client certificate with certain ASN.1 tag values.

OpenSSL 0.9.6e uses assertions when detecting buffer overflow attacks instead of less severe mechanisms, which allows remote attackers to cause a denial of service (crash) via certain messages that cause OpenSSL to abort from a failed assertion, as demonstrated using SSLv2 CLIENT_MASTER_KEY messages, which are not properly handled in s2_srvr.c.

Multiple "buffer management errors" in OpenSSH before 3.7.1 may allow attackers to cause a denial of service or execute arbitrary code using (1) buffer_init in buffer.c, (2) buffer_free in buffer.c, or (3) a separate function in channels.c, a different vulnerability than CVE-2003-0693.

"Memory bugs" in OpenSSH 3.7.1 and earlier, with unknown impact, a different set of vulnerabilities than CVE-2003-0693 and CVE-2003-0695.

A "buffer management error" in buffer_append_space of buffer.c for OpenSSH before 3.7 may allow remote attackers to execute arbitrary code by causing an incorrect amount of memory to be freed and corrupting the heap, a different vulnerability than CVE-2003-0695.

OpenSSH 3.6.1 and earlier, when restricting host access by numeric IP addresses and with VerifyReverseMapping disabled, allows remote attackers to bypass "from=" and "user@host" address restrictions by connecting to a host from a system whose reverse DNS hostname contains the numeric IP address.

OpenSSH-portable (OpenSSH) 3.6.1p1 and earlier with PAM support enabled immediately sends an error message when a user does not exist, which allows remote attackers to determine valid usernames via a timing attack.

OpenSSL does not use RSA blinding by default, which allows local and remote attackers to obtain the server's private key by determining factors using timing differences on (1) the number of extra reductions during Montgomery reduction, and (2) the use of different integer multiplication algorithms ("Karatsuba" and normal).

The SSL and TLS components for OpenSSL 0.9.6i and earlier, 0.9.7, and 0.9.7a allow remote attackers to perform an unauthorized RSA private key operation via a modified Bleichenbacher attack that uses a large number of SSL or TLS connections using PKCS #1 v1.5 padding that cause OpenSSL to leak information regarding the relationship between ciphertext and the associated plaintext, aka the "Klima-Pokorny-Rosa attack."

ssl3_get_record in s3_pkt.c for OpenSSL before 0.9.7a and 0.9.6 before 0.9.6i does not perform a MAC computation if an incorrect block cipher padding is used, which causes an information leak (timing discrepancy) that may make it easier to launch cryptographic attacks that rely on distinguishing between padding and MAC verification errors, possibly leading to extraction of the original plaintext, aka the "Vaudenay timing attack."

sshd in OpenSSH 3.2.2, when using YP with netgroups and under certain conditions, may allow users to successfully authenticate and log in with another user's password.

The ASN1 library in OpenSSL 0.9.6d and earlier, and 0.9.7-beta2 and earlier, allows remote attackers to cause a denial of service via invalid encodings.

Buffer overflow in OpenSSL 0.9.7 before 0.9.7-beta3, with Kerberos enabled, allows attackers to execute arbitrary code via a long master key.

Buffer overflows in OpenSSL 0.9.6d and earlier, and 0.9.7-beta2 and earlier, allow remote attackers to execute arbitrary code via (1) a large client master key in SSL2 or (2) a large session ID in SSL3.

OpenSSL 0.9.6d and earlier, and 0.9.7-beta2 and earlier, does not properly handle ASCII representations of integers on 64 bit platforms, which could allow attackers to cause a denial of service and possibly execute arbitrary code.

Buffer overflow in sshd in OpenSSH 2.3.1 through 3.3 may allow remote attackers to execute arbitrary code via a large number of responses during challenge response authentication when OpenBSD is using PAM modules with interactive keyboard authentication (PAMAuthenticationViaKbdInt).

Integer overflow in sshd in OpenSSH 2.9.9 through 3.3 allows remote attackers to execute arbitrary code during challenge response authentication (ChallengeResponseAuthentication) when OpenSSH is using SKEY or BSD_AUTH authentication.

Buffer overflow in OpenSSH before 2.9.9, and 3.x before 3.2.1, with Kerberos/AFS support and KerberosTgtPassing or AFSTokenPassing enabled, allows remote and local authenticated users to gain privileges.

Off-by-one error in the channel code of OpenSSH 2.0 through 3.0.2 allows local users or remote malicious servers to gain privileges.

SSH protocol 2 (aka SSH-2) public key authentication in the development snapshot of OpenSSH 2.3.1, available from 2001-01-18 through 2001-02-08, does not perform a challenge-response step to ensure that the client has the proper private key, which allows remote attackers to bypass authentication as other users by supplying a public key from that user's authorized_keys file.

OpenSSH before 3.0.1 with Kerberos V enabled does not properly authenticate users, which could allow remote attackers to login unchallenged.

OpenSSH 3.0.1 and earlier with UseLogin enabled does not properly cleanse critical environment variables such as LD_PRELOAD, which allows local users to gain root privileges.

OpenSSH before 2.9.9, when running sftp using sftp-server and using restricted keypairs, allows remote authenticated users to bypass authorized_keys2 command= restrictions using sftp commands.

OpenSSH before 2.9.9, while using keypairs and multiple keys of different types in the ~/.ssh/authorized_keys2 file, may not properly handle the "from" option associated with a key, which could allow remote attackers to login from unauthorized IP addresses.

The "echo simulation" traffic analysis countermeasure in OpenSSH before 2.9.9p2 sends an additional echo packet after the password and carriage return is entered, which could allow remote attackers to determine that the countermeasure is being used.

libutil in OpenSSH on FreeBSD 4.4 and earlier does not drop privileges before verifying the capabilities for reading the copyright and welcome files, which allows local users to bypass the capabilities checks and read arbitrary files by specifying alternate copyright or welcome files.

The SSH protocols 1 and 2 (aka SSH-2) as implemented in OpenSSH and other packages have various weaknesses which can allow a remote attacker to obtain the following information via sniffing: (1) password lengths or ranges of lengths, which simplifies brute force password guessing, (2) whether RSA or DSA authentication is being used, (3) the number of authorized_keys in RSA authentication, or (4) the lengths of shell commands.

OpenSSH version 2.9 and earlier, with X forwarding enabled, allows a local attacker to delete any file named 'cookies' via a symlink attack.

The Pseudo-Random Number Generator (PRNG) in SSLeay and OpenSSL before 0.9.6b allows attackers to use the output of small PRNG requests to determine the internal state information, which could be used by attackers to predict future pseudo-random numbers.

Implementations of SSH version 1.5, including (1) OpenSSH up to version 2.3.0, (2) AppGate, and (3) ssh-1 up to version 1.2.31, in certain configurations, allow a remote attacker to decrypt and/or alter traffic via a "Bleichenbacher attack" on PKCS#1 version 1.5.

OpenSSH 2.9 and earlier does not initiate a Pluggable Authentication Module (PAM) session if commands are executed with no pty, which allows local users to bypass resource limits (rlimits) set in pam.d.

CORE SDI SSH1 CRC-32 compensation attack detector allows remote attackers to execute arbitrary commands on an SSH server or client via an integer overflow.

OpenSSH SSH client before 2.3.0 does not properly disable X11 or agent forwarding, which could allow a malicious SSH server to gain access to the X11 display and sniff X11 events, or gain access to the ssh-agent.