CVE-2025-9820

A flaw was found in the GnuTLS library, specifically in the gnutlspkcs11token_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.

Database specific

{
    "cna_assigner": "redhat",
    "cwe_ids": [
        "CWE-121"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/9xxx/CVE-2025-9820.json"
}

References

Affected packages

Git / gitlab.com/gnutls/gnutls

Affected ranges

Type

GIT

Repo

https://gitlab.com/gnutls/gnutls

Events

Introduced

513570a57da9d354379eef1163385d87aedd4109

Fixed

1d56f96f6ab5034d677136b9d50b5a75dff0faf5

Database specific

Show details

{
    "extracted_events": [
        {
            "introduced": "3.8.1"
        },
        {
            "last_affected": "3.8.1"
        },
        {
            "introduced": "3.8.2"
        },
        {
            "last_affected": "3.8.2"
        },
        {
            "introduced": "3.8.3"
        },
        {
            "last_affected": "3.8.3"
        },
        {
            "introduced": "3.8.4"
        },
        {
            "last_affected": "3.8.4"
        },
        {
            "introduced": "3.8.5"
        },
        {
            "last_affected": "3.8.5"
        },
        {
            "introduced": "3.8.6"
        },
        {
            "last_affected": "3.8.6"
        },
        {
            "introduced": "3.8.7"
        },
        {
            "last_affected": "3.8.7"
        },
        {
            "introduced": "3.8.8"
        },
        {
            "last_affected": "3.8.8"
        },
        {
            "introduced": "3.8.9"
        },
        {
            "last_affected": "3.8.9"
        },
        {
            "introduced": "3.8.10"
        },
        {
            "last_affected": "3.8.10"
        }
    ],
    "source": [
        "AFFECTED_FIELD",
        "REFERENCES"
    ]
}

Affected versions

3.*

3.8.1

3.8.10

3.8.2

3.8.3

3.8.4

3.8.5

3.8.6

3.8.7

3.8.8

3.8.9

Database specific

vanir_signatures_modified

"2026-08-23T10:47:15Z"

source

"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2025-9820.json"

vanir_signatures

[
    {
        "target": {
            "file": "lib/pkcs11_write.c"
        },
        "deprecated": false,
        "id": "CVE-2025-9820-2f514dfb",
        "signature_version": "v1",
        "digest": {
            "threshold": 0.9,
            "line_hashes": [
                "203081701998267077212086687325320656047",
                "181103679989110600517533548016277704131",
                "39853057649325964027587234063574987404",
                "259048303717493519631185376627170807634",
                "235519305165135146109306515938527170000",
                "15365237184004671114243159335111336950",
                "128494245172431755117396483110562105716",
                "44347100990748648967188547802763753138",
                "328331381237090027273525864829690989806",
                "255687099527695671086163998843993578170",
                "226269730992432168968068826384392231200"
            ]
        },
        "source": "https://gitlab.com/gnutls/gnutls@1d56f96f6ab5034d677136b9d50b5a75dff0faf5",
        "signature_type": "Line"
    },
    {
        "target": {
            "file": "lib/pkcs11_write.c",
            "function": "gnutls_pkcs11_token_init"
        },
        "deprecated": false,
        "id": "CVE-2025-9820-ef29652e",
        "signature_version": "v1",
        "digest": {
            "function_hash": "129252198033229729266867875486069486085",
            "length": 734.0
        },
        "source": "https://gitlab.com/gnutls/gnutls@1d56f96f6ab5034d677136b9d50b5a75dff0faf5",
        "signature_type": "Function"
    }
]