CVEvulnerability
CVE-2026-103603
8.7 HIGH
Official page ↗
- Status
- Analyzed
- Published
- 2026-10-02
- Last modified
- 2026-10-28
- Assigner
- 91579145-5d7b-4cc5-b925-a0262ff19630
- CVSS 4.0 (91579145-5d7b-4cc5-b925-a0262ff19630)
- 8.7 HIGH — CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- CVSS 3.1 ([email protected])
- 7.5 HIGH — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- Weaknesses
- CWE-789
Description
Memory allocation with excessive size value in the HSS/LMS signature code (HssPublicKeyParameters, HssSignature) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker who can supply both an HSS public key and a signature to cause a denial of service through memory exhaustion via a public key encoding with an excessive level count, because the level count L read when parsing an HSS public key was not checked against the RFC 8554 maximum of 8, and signature parsing then allocated an array of L - 1 entries before reading any further signature data. A single verification can commit up to about 17 GB of memory or fail with an OutOfMemoryException.
Affected configurations
• bouncycastle bc-csharp (< 2.7.0)
Related
Weakness · CWE (1)
- CWE-789 Memory Allocation with Excessive Size Value weakness