Answer in brief
CVE-2025-9820 records a Medium severity (CVSS 4.0) vulnerability in Gnutls: stack-based buffer overflow in gnutls_pkcs11_token_init() function. The current sources do not mark it as known exploited. The current feed maps Siemens/SIMATIC CN 4100 (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
Answer in brief
CVE-2025-9820 records a Medium severity (CVSS 4.0) vulnerability in Gnutls: stack-based buffer overflow in gnutls_pkcs11_token_init() function. The current sources do not mark it as known exploited. The current feed maps Siemens/SIMATIC CN 4100 (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 4.0. 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 Siemens/SIMATIC CN 4100 (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Siemens/SIMATIC CN 4100generic | >=0 <V5.0 | V5.0 |
Published upstream
Jan 26, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
A flaw was found in the GnuTLS library, specifically in the gnutls_pkcs11_token_init() function that handles PKCS#11 token initialization. When a token label longer than expected is processed, the function writes past the end of a fixed-size stack buffer. This programming error can cause the application using GnuTLS to crash or, in certain conditions, be exploited for code execution. As a result, systems or applications relying on GnuTLS may be vulnerable to a denial of service or local privilege escalation attacks.
Quoted source text, attributed separately from HOL analysis.
CVSS is 4.0. 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 Siemens/SIMATIC CN 4100 (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| Siemens/SIMATIC CN 4100generic | >=0 <V5.0 | V5.0 |
Published upstream
Jan 26, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jun 30, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jun 25, 2026
A flaw was found in the GnuTLS library, specifically in the gnutls_pkcs11_token_init() function that handles PKCS#11 token initialization. When a token label longer than expected is processed, the function writes past the end of a fixed-size stack buffer. This programming error can cause the application using GnuTLS to crash or, in certain conditions, be exploited for code execution. As a result, systems or applications relying on GnuTLS may be vulnerable to a denial of service or local privilege escalation attacks.
Quoted source text, attributed separately from HOL analysis.