CVE-2026-102486
Description
A flaw was found in NTPsec. This flaw allows a remote attacker to cause a Denial of Service (DoS) by crashing the NTP daemon. The issue is caused by an out-of-bounds read vulnerability when parsing Network Time Security (NTS) extension fields that contain an Authenticator and Encrypted Extension Fields (AEEF) field with an oversized nonce length.
Statement
An out-of-bounds read flaw was found in NTPsec ntpd NTS extension field parsing. A remote attacker able to complete an NTS-KE TLS handshake and obtain an NTS cookie can send a crafted NTP packet with an oversized nonce length in an NTS AEEF field, causing ntpd to crash (denial of service) on servers with NTS enabled. Versions 1.1.4 through 1.2.5 are affected; the issue is fixed in 1.2.6.
Mitigation
Disable NTS in ntpd configuration or upgrade to ntpsec 1.2.6.
Understanding the Weakness (CWE)
Confidentiality
Technical Impact: Read Memory
An attacker could get secret values such as cryptographic keys, PII, memory addresses, or other information that could be used in additional attacks.
Confidentiality
Technical Impact: Bypass Protection Mechanism
Out-of-bounds memory could contain memory addresses or other information that can be used to bypass ASLR and other protection mechanisms in order to improve the reliability of exploiting a separate weakness for code execution.
Availability
Technical Impact: DoS: Crash, Exit, or Restart
An attacker could cause a segmentation fault or crash by causing memory to be read outside of the bounds of the buffer. This is especially likely when the code reads a variable amount of data and assumes that a sentinel exists to stop the read operation, such as a NUL in a string.
Other
Technical Impact: Varies by Context
The read operation could produce other undefined or unexpected results.
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