CVE-2026-75806
MediumCVSS 5.3Exploitation Probability (EPSS)
Low risk31th percentile - higher than 31% of all known CVEs
Summary
An established DTLS 1.2 association using an AEAD cipher suite can be terminated by a single unauthenticated datagram whose encrypted fragment is shorter than the mandatory explicit IV and authentication tag overhead. The record layer passes the record length to the cipher before checking it is long enough, causing an internal error instead of treating the record as failed authentication.
Risk Assessment
An attacker who can send a datagram to an existing DTLS 1.2 association can tear it down without knowing any key material, causing a denial of service limited to that association. There is no memory safety or confidentiality impact.
Recommendation
Apply the vendor patch that validates record length against explicit IV and tag length before AEAD processing, so DTLS silently discards short records. Update the TLS/DTLS library to a patched version.
Other vulnerabilities in OpenSSL
See all- CVE-2016-8610High
A denial of service flaw was found in OpenSSL 0.9.8, 1.0.1, 1.0.2 through 1.0.2h, and 1.1.0 in the way the TLS/SSL protocol defined processing of ALERT packets during a connection handshake. A remote attacker could use this flaw to make a TLS/SSL server consume an excessive amount of CPU and fail to accept connections from other clients.
- CVE-2017-3731High
CVE-2017-3731 affects SSL/TLS servers and clients running on 32-bit hosts that may crash due to an out-of-bounds read caused by a truncated packet. For OpenSSL 1.1.0, the crash can be triggered using the CHACHA20/POLY1305 cipher, and for OpenSSL 1.0.2 using RC4-MD5.
- CVE-2017-3730High
In OpenSSL 1.1.0 before 1.1.0d, a malicious server can supply bad parameters for a DHE or ECDHE key exchange, leading to the client attempting to dereference a NULL pointer, resulting in a client crash.
- CVE-2016-7054High
In OpenSSL 1.1.0 before 1.1.0c, TLS connections using *-CHACHA20-POLY1305 ciphersuites are susceptible to a DoS attack by corrupting larger payloads. This can result in an OpenSSL crash.
- CVE-2016-7052High
OpenSSL 1.0.2i has a vulnerability that allows remote attackers to cause application crashes by triggering a CRL operation, leading to a NULL pointer dereference.
- CVE-2016-6305High
The ssl3_read_bytes function in OpenSSL 1.1.0 before version 1.1.0a allows remote attackers to cause a denial of service (infinite loop) by triggering a zero-length record in an SSL_peek call.
- CVE-2016-6304High
Multiple memory leaks in t1_lib.c in OpenSSL before 1.0.1u, 1.0.2 before 1.0.2i, and 1.1.0 before 1.1.0a allow remote attackers to cause a denial of service (memory consumption) via large OCSP Status Request extensions.
- CVE-2016-6302High
The tls_decrypt_ticket function in OpenSSL before 1.1.0 does not consider the HMAC size during validation of the ticket length, allowing remote attackers to cause a denial of service via a ticket that is too short.
- CVE-2016-2179High
The DTLS implementation in OpenSSL before 1.1.0 does not properly restrict the lifetime of queue entries associated with unused out-of-order messages. This allows remote attackers to cause a denial of service (memory consumption) by maintaining many crafted DTLS sessions simultaneously.
- CVE-2016-2176High
The X509_NAME_oneline function in OpenSSL before 1.0.1t and 1.0.2 before 1.0.2h allows remote attackers to obtain sensitive information from process stack memory or cause a denial of service (buffer over-read) via crafted EBCDIC ASN.1 data.
Original NVD description (English source)
Issue summary: An established DTLS 1.2 association using an AEAD cipher suite can be terminated by a single unauthenticated datagram whose encrypted fragment is shorter than the mandatory explicit IV and authentication tag overhead. Impact summary: An attacker who can send a datagram that is routed to an existing DTLS 1.2 association can tear that association down without knowing any key material. This is a Denial of Service limited to the targeted association. There is no memory safety or confidentiality impact. CWE: CWE-1284: Improper Validation of Specified Quantity in Input Description: In TLS 1.2 and DTLS 1.2 every record protected by an AEAD cipher suite carries an explicit IV followed by the ciphertext and an authentication tag. When decrypting such a record the record layer passed the record length to the cipher implementation before checking that the record was long enough to contain the explicit IV and the tag. For a record shorter than that overhead the cipher implementation rejected the impossible length, and the record layer treated this as an internal failure and raised a fatal internal_error alert instead of treating the record as one that failed authentication. In TLS 1.2 the same record causes a fatal internal_error alert instead of the expected bad_record_mac alert. Since any undecryptable record already terminates a TLS connection, this is a protocol conformance issue rather than a security issue in TLS. The fix validates the record length against the explicit IV and tag length before any AEAD processing, so that TLS reports bad_record_mac and DTLS silently discards the record. FIPS impact: no The affected code is outside the FIPS module boundary.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

