Answer in brief
CVE-2026-12852 records a High severity (CVSS 8.7) vulnerability in MLS wire decoder allocates attacker-declared opaque length before bounds check. The current sources do not mark it as known exploited. The current feed maps Legion of the Bouncy Castle Inc./BC-JAVA (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Legion of the Bouncy Castle Inc./BC-JAVA (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Legion of the Bouncy Castle Inc./BC-JAVAgeneric | >=1.73 <1.85 | 1.85 |
Published upstream
Aug 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 3, 2026
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-12852 records a High severity (CVSS 8.7) vulnerability in MLS wire decoder allocates attacker-declared opaque length before bounds check. The current sources do not mark it as known exploited. The current feed maps Legion of the Bouncy Castle Inc./BC-JAVA (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 8.7. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps Legion of the Bouncy Castle Inc./BC-JAVA (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Legion of the Bouncy Castle Inc./BC-JAVAgeneric | >=1.73 <1.85 | 1.85 |
Published upstream
Aug 3, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Aug 4, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Aug 3, 2026
In Bouncy Castle for Java before 1.85, MLS wire decoder allocates attacker-declared opaque length before bounds check.
Quoted source text, attributed separately from HOL analysis.