Simple authentication protocols are subject to reflection attacks if a malicious user can use the target machine to impersonate a trusted user.
View on MITREA mutual authentication protocol requires each party to respond to a random challenge by the other party by encrypting it with a pre-shared key. Often, however, such protocols employ the same pre-shared key for communication with a number of different entities. A malicious user or an attacker can easily compromise this protocol without possessing the correct key by employing a reflection attack on the protocol. Reflection attacks capitalize on mutual authentication schemes in order to trick the target into revealing the secret shared between it and another valid user. In a basic mutual-authentication scheme, a secret is known to both the valid user and the server; this allows them to authenticate. In order that they may verify this shared secret without sending it plainly over the wire, they utilize a Diffie-Hellman-style scheme in which they each pick a value, then request the hash of that value as keyed by the shared secret. In a reflection attack, the attacker claims to be a valid user and requests the hash of a random value from the server. When the server returns this value and requests its own value to be hashed, the attacker opens another connection to the server. This time, the hash requested by the attacker is the value which the server requested in the first connection. When the server returns this hashed value, it is used in the first connection, authenticating the attacker successfully as the impersonated valid user.
The primary result of reflection attacks is successful authentication with a target machine -- as an impersonated user.
Use different keys for the initiator and responder or of a different type of challenge for the initiator and responder.
Let the initiator prove its identity before proceeding.
No detection method information available for this CWE.
The following example demonstrates the weakness.
unsigned char *simple_digest(char *alg,char *buf,unsigned int len, int *olen) {const EVP_MD *m;EVP_MD_CTX ctx;unsigned char *ret;OpenSSL_add_all_digests();if (!(m = EVP_get_digestbyname(alg))) return NULL;if (!(ret = (unsigned char*)malloc(EVP_MAX_MD_SIZE))) return NULL;EVP_DigestInit(&ctx, m);EVP_DigestUpdate(&ctx,buf,len);EVP_DigestFinal(&ctx,ret,olen);return ret;}unsigned char *generate_password_and_cmd(char *password_and_cmd) {simple_digest("sha1",password,strlen(password_and_cmd)...);}The following example demonstrates the weakness.
String command = new String("some cmd to execute & the password") MessageDigest encer = MessageDigest.getInstance("SHA");encer.update(command.getBytes("UTF-8"));byte[] digest = encer.digest();web server includes the nonce in its challenge/response mechanism, allowing a replay attack
View Detailsproduct authentication succeeds if user-provided MD5 hash matches the hash in its database; this can be subjected to replay attacks.
View DetailsCWE-301: Reflection Attack in an Authentication Protocol is a Common Weakness Enumeration (CWE) entry maintained by MITRE. Simple authentication protocols are subject to reflection attacks if a malicious user can use the target machine to impersonate a trusted user. A mutual authentication protocol requires each party to respond to a random challenge by the other party by encrypting it with a pre-shared key. Often, however, such protocols employ the same pre-shared key for communication with a number of different entities. A malicious user or an attacker can easily compromise this protocol without possessing the correct key by employing a reflection attack on the protocol. Reflection attacks capitalize on mutual authentication schemes in order to trick the target into revealing the secret shared between it and another valid user. In a basic mutual-authentication scheme, a secret is known to both the valid user and the server; this allows them to authenticate. In order that they may verify this shared secret without sending it plainly over the wire, they utilize a Diffie-Hellman-style scheme in which they each pick a value, then request the hash of that value as keyed by the shared secret. In a reflection attack, the attacker claims to be a valid user and requests the hash of a random value from the server. When the server returns this value and requests its own value to be hashed, the attacker opens another connection to the server. This time, the hash requested by the attacker is the value which the server requested in the first connection. When the server returns this hashed value, it is used in the first connection, authenticating the attacker successfully as the impersonated valid user.
If exploited, CWE-301 (Reflection Attack in an Authentication Protocol) it can compromise Access Control, leading to outcomes such as Gain Privileges or Assume Identity.
Recommended mitigations for CWE-301 include: Use different keys for the initiator and responder or of a different type of challenge for the initiator and responder. Let the initiator prove its identity before proceeding.
CWE-301 commonly affects Not Language-Specific. Note that weaknesses are often language-agnostic patterns, so secure coding practices apply broadly.
MITRE documents real CVEs mapped to CWE-301, including CVE-2024-11022 and CVE-2005-3435. You can look up the full details of each CVE, including CVSS scores and remediation guidance, on our CVE Lookup tool.
A CWE (Common Weakness Enumeration) like CWE-301 describes a category of software weakness — the underlying flaw type. A CVE (Common Vulnerabilities and Exposures) identifies a specific, real-world vulnerability in a particular product. In short, a CWE is the kind of mistake, and a CVE is an instance of that mistake being found in software.