Dashboard / CVE-2026-63570

CVE-2026-63570

HIGH
MEDIUM Priority: 0.02 BB Relevance: 64/100
Published: 2026-10-02 Modified: 2026-10-28 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: Passive
S: X
AT: None
VC: None
VI: None
VA: High

Description

Loop with unreachable exit condition in Pkcs12Store.GetCertificateChain in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can supply a crafted PKCS#12 file to an application that loads it and requests a key entry's certificate chain to cause a denial of service, in which the call never returns and consumes CPU and memory until an OutOfMemoryException, via certificates whose issuer links form a cycle, for example two certificates whose AuthorityKeyIdentifier extensions each identify the other's public key. This happens because the chain-building loop stops only when no issuer is found or a certificate links to itself, and keeps no record of certificates already visited. The key-identifier links are followed without checking signatures.

Weakness Classification (1)

Affected Software (2)

VendorProductVersion
bouncycastle bc-csharp < 2.7.0
bouncycastle bc-csharp < 2.7.0

References & Advisories (2)

Bug Bounty Relevance

64 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity

CVSS Score

7.1 / 10.0 v4.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/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

EPSS — Exploitation Probability

0.23%
Raw Score 0.002260
Percentile 13.4%
Date 2026-10-29

EPSS Trend

2026-10-29
0.00226
2026-10-28
0.00213

Intelligence Sources

nvd ref →

External Links