CVE-2026-63566 (GCVE-0-2026-63566)
Vulnerability from cvelistv5
Published
2026-10-02 06:57
Modified
2026-10-02 18:08
Severity ?
VLAI Severity ?
EPSS score ?
CWE
- CWE-789 - Memory Allocation with Excessive Size Value
Summary
Memory allocation with excessive size value in the DTLS handshake reassembly (DtlsReliableHandshake, DtlsReassembler) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated DTLS peer to cause a denial of service through memory exhaustion via crafted handshake message fragments, because the reassembly buffer for each incoming handshake message was allocated at the 24-bit length declared in the fragment header, without the check against the peer's maximum handshake message size that TLS already applied. A fragment carrying no payload can force an allocation of almost 16 MB, for each of up to 16 pending messages per handshake, before the handshake is authenticated. DTLS servers and DTLS clients are both affected; TLS is not.
References
Impacted products
| Vendor | Product | Version | ||
|---|---|---|---|---|
| Legion of the Bouncy Castle Inc. | bc-csharp |
Version: 0 ≤ |
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
- Confirmed: The vulnerability is confirmed from an analyst perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
- Patched: This vulnerability was successfully patched by the user reporting the sighting.
- Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
- Not confirmed: The user expresses doubt about the veracity of the vulnerability.
- Not patched: This vulnerability was not successfully patched by the user reporting the sighting.
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