Bug 2565815 (CVE-2026-121505)

Summary: CVE-2026-121505 ntpsec: ntpsec: Information disclosure via malformed NTS-KE response record
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
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Priority: low    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in NTPsec. A malicious Network Time Security Key Exchange (NTS-KE) server can cause information disclosure by sending a response record with a declared length exceeding the data received. This triggers an out-of-bounds read in the client response parser, allowing the server to retrieve sensitive stack memory, such as internal pointers that weaken Address Space Layout Randomization (ASLR), which the client sends back in cleartext.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Description OSIDB Bzimport 2026-11-03 14:36:56 UTC
An out-of-bounds read in the NTS-KE client response parser (nts_client_process_response_core) in NTPsec before 1.2.4 allows a malicious NTS-KE server to read the client's stack memory, including pointers that defeat ASLR, which the client then sends in cleartext as NTS cookies, via an NTS-KE record whose declared length exceeds the data received.