Vulnerability-Lookup

BDU:2025-10339 (CVE-2025-20127)

Vulnerability from fstec – Published: 2025-08-27 – Updated: 2025-08-27 – View on bdu.fstec.ru Fixed

Title

Summary

Уязвимость функции обработки TLS микропрограммного обеспечения межсетевых экранов Cisco Adaptive Security Appliance (ASA) и Cisco Firepower Threat Defense (FTD) серий Firepower 3100 Series и Firepower 4200 Series связана с некорректной зачисткой или освобождением ресурсов. Эксплуатация уязвимости может позволить нарушителю, действующему удаленно, вызвать отказ в обслуживании

Severity

6.8 (Medium) CVSS 2.0


                      
                        AV:N/AC:L/Au:S/C:N/I:N/A:C

7.7 (High) CVSS 3.1


                      
                        CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

Class

Code vulnerability

Status

Confirmed by the vendor

Exploitation

Resource exhaustion

Incidents

Being clarified

Remediation

Software update

CWE

CWE-404 - Некорректная зачистка или освобождение ресурсов

Aliases

CVE-2025-20127

References

1 reference

URL
https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/c…

Impacted products

2 products from 2 vendors

Vendors

Cisco Systems, Inc.

Products

Adaptive Security Appliance, Firepower Threat Defense

Versions

9.20.1 (Adaptive Security Appliance), 9.20.1.5 (Adaptive Security Appliance), 9.20.2 (Adaptive Security Appliance), 7.4.0 (Firepower Threat Defense), 7.4.1 (Firepower Threat Defense), 9.20.2.10 (Adaptive Security Appliance), 9.20.2.21 (Adaptive Security Appliance), 9.20.2.22 (Adaptive Security Appliance), 7.4.1.1 (Firepower Threat Defense), 9.20.3 (Adaptive Security Appliance), 7.4.2 (Firepower Threat Defense), 9.20.3.4 (Adaptive Security Appliance), 9.20.3.7 (Adaptive Security Appliance), 9.22.1.1 (Adaptive Security Appliance), 7.4.2.1 (Firepower Threat Defense), 7.6.0 (Firepower Threat Defense)

Product types

Network appliance software, Appliance software

Mitigations

Использование рекомендаций: https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3100_4200_tlsdos-2yNSCd54

JSON

To clipboard

{
  "CVSS 2.0": "AV:N/AC:L/Au:S/C:N/I:N/A:C",
  "CVSS 3.0": "AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H",
  "CVSS 4.0": null,
  "remediation_\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": null,
  "remediation_\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435": null,
  "\u0412\u0435\u043d\u0434\u043e\u0440 \u041f\u041e": "Cisco Systems, Inc.",
  "\u0412\u0435\u0440\u0441\u0438\u044f \u041f\u041e": "9.20.1 (Adaptive Security Appliance), 9.20.1.5 (Adaptive Security Appliance), 9.20.2 (Adaptive Security Appliance), 7.4.0 (Firepower Threat Defense), 7.4.1 (Firepower Threat Defense), 9.20.2.10 (Adaptive Security Appliance), 9.20.2.21 (Adaptive Security Appliance), 9.20.2.22 (Adaptive Security Appliance), 7.4.1.1 (Firepower Threat Defense), 9.20.3 (Adaptive Security Appliance), 7.4.2 (Firepower Threat Defense), 9.20.3.4 (Adaptive Security Appliance), 9.20.3.7 (Adaptive Security Appliance), 9.22.1.1 (Adaptive Security Appliance), 7.4.2.1 (Firepower Threat Defense), 7.6.0 (Firepower Threat Defense)",
  "\u0412\u043e\u0437\u043c\u043e\u0436\u043d\u044b\u0435 \u043c\u0435\u0440\u044b \u043f\u043e \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044e": "\u0418\u0441\u043f\u043e\u043b\u044c\u0437\u043e\u0432\u0430\u043d\u0438\u0435 \u0440\u0435\u043a\u043e\u043c\u0435\u043d\u0434\u0430\u0446\u0438\u0439:\nhttps://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3100_4200_tlsdos-2yNSCd54",
  "\u0414\u0430\u0442\u0430 \u0432\u044b\u044f\u0432\u043b\u0435\u043d\u0438\u044f": "14.08.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u043e\u0441\u043b\u0435\u0434\u043d\u0435\u0433\u043e \u043e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u044f": "27.08.2025",
  "\u0414\u0430\u0442\u0430 \u043f\u0443\u0431\u043b\u0438\u043a\u0430\u0446\u0438\u0438": "27.08.2025",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440": "BDU:2025-10339",
  "\u0418\u0434\u0435\u043d\u0442\u0438\u0444\u0438\u043a\u0430\u0442\u043e\u0440\u044b \u0434\u0440\u0443\u0433\u0438\u0445 \u0441\u0438\u0441\u0442\u0435\u043c \u043e\u043f\u0438\u0441\u0430\u043d\u0438\u0439 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "CVE-2025-20127",
  "\u0418\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f \u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0430",
  "\u041a\u043b\u0430\u0441\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u043a\u043e\u0434\u0430",
  "\u041d\u0430\u0437\u0432\u0430\u043d\u0438\u0435 \u041f\u041e": "Adaptive Security Appliance, Firepower Threat Defense",
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u041e\u0421 \u0438 \u0442\u0438\u043f \u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0439 \u043f\u043b\u0430\u0442\u0444\u043e\u0440\u043c\u044b": null,
  "\u041d\u0430\u0438\u043c\u0435\u043d\u043e\u0432\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0438 TLS \u043c\u0438\u043a\u0440\u043e\u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f \u043c\u0435\u0436\u0441\u0435\u0442\u0435\u0432\u044b\u0445 \u044d\u043a\u0440\u0430\u043d\u043e\u0432 Cisco Adaptive Security Appliance (ASA) \u0438 Cisco Firepower Threat Defense (FTD) \u0441\u0435\u0440\u0438\u0439 Firepower 3100 Series \u0438 Firepower 4200 Series, \u043f\u043e\u0437\u0432\u043e\u043b\u044f\u044e\u0449\u0430\u044f \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041d\u0430\u043b\u0438\u0447\u0438\u0435 \u044d\u043a\u0441\u043f\u043b\u043e\u0439\u0442\u0430": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "\u041d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u0430\u044f \u0437\u0430\u0447\u0438\u0441\u0442\u043a\u0430 \u0438\u043b\u0438 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432 (CWE-404)",
  "\u041e\u043f\u0438\u0441\u0430\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0423\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u044c \u0444\u0443\u043d\u043a\u0446\u0438\u0438 \u043e\u0431\u0440\u0430\u0431\u043e\u0442\u043a\u0438 TLS \u043c\u0438\u043a\u0440\u043e\u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f \u043c\u0435\u0436\u0441\u0435\u0442\u0435\u0432\u044b\u0445 \u044d\u043a\u0440\u0430\u043d\u043e\u0432 Cisco Adaptive Security Appliance (ASA) \u0438 Cisco Firepower Threat Defense (FTD) \u0441\u0435\u0440\u0438\u0439 Firepower 3100 Series \u0438 Firepower 4200 Series \u0441\u0432\u044f\u0437\u0430\u043d\u0430 \u0441 \u043d\u0435\u043a\u043e\u0440\u0440\u0435\u043a\u0442\u043d\u043e\u0439 \u0437\u0430\u0447\u0438\u0441\u0442\u043a\u043e\u0439 \u0438\u043b\u0438 \u043e\u0441\u0432\u043e\u0431\u043e\u0436\u0434\u0435\u043d\u0438\u0435\u043c \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432. \u042d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u044f \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438 \u043c\u043e\u0436\u0435\u0442 \u043f\u043e\u0437\u0432\u043e\u043b\u0438\u0442\u044c \u043d\u0430\u0440\u0443\u0448\u0438\u0442\u0435\u043b\u044e, \u0434\u0435\u0439\u0441\u0442\u0432\u0443\u044e\u0449\u0435\u043c\u0443 \u0443\u0434\u0430\u043b\u0435\u043d\u043d\u043e, \u0432\u044b\u0437\u0432\u0430\u0442\u044c \u043e\u0442\u043a\u0430\u0437 \u0432 \u043e\u0431\u0441\u043b\u0443\u0436\u0438\u0432\u0430\u043d\u0438\u0438",
  "\u041f\u043e\u0441\u043b\u0435\u0434\u0441\u0442\u0432\u0438\u044f \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": null,
  "\u041f\u0440\u043e\u0447\u0430\u044f \u0438\u043d\u0444\u043e\u0440\u043c\u0430\u0446\u0438\u044f": null,
  "\u0421\u0432\u044f\u0437\u044c \u0441 \u0438\u043d\u0446\u0438\u0434\u0435\u043d\u0442\u0430\u043c\u0438 \u0418\u0411": "\u0414\u0430\u043d\u043d\u044b\u0435 \u0443\u0442\u043e\u0447\u043d\u044f\u044e\u0442\u0441\u044f",
  "\u0421\u043e\u0441\u0442\u043e\u044f\u043d\u0438\u0435 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041e\u043f\u0443\u0431\u043b\u0438\u043a\u043e\u0432\u0430\u043d\u0430",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u0443\u0441\u0442\u0440\u0430\u043d\u0435\u043d\u0438\u044f": "\u041e\u0431\u043d\u043e\u0432\u043b\u0435\u043d\u0438\u0435 \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e\u0433\u043e \u043e\u0431\u0435\u0441\u043f\u0435\u0447\u0435\u043d\u0438\u044f",
  "\u0421\u043f\u043e\u0441\u043e\u0431 \u044d\u043a\u0441\u043f\u043b\u0443\u0430\u0442\u0430\u0446\u0438\u0438": "\u0418\u0441\u0447\u0435\u0440\u043f\u0430\u043d\u0438\u0435 \u0440\u0435\u0441\u0443\u0440\u0441\u043e\u0432",
  "\u0421\u0441\u044b\u043b\u043a\u0438 \u043d\u0430 \u0438\u0441\u0442\u043e\u0447\u043d\u0438\u043a\u0438": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3100_4200_tlsdos-2yNSCd54",
  "\u0421\u0442\u0430\u0442\u0443\u0441 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u041f\u043e\u0434\u0442\u0432\u0435\u0440\u0436\u0434\u0435\u043d\u0430 \u043f\u0440\u043e\u0438\u0437\u0432\u043e\u0434\u0438\u0442\u0435\u043b\u0435\u043c",
  "\u0422\u0438\u043f \u041f\u041e": "\u041f\u041e \u0441\u0435\u0442\u0435\u0432\u043e\u0433\u043e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e-\u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430, \u041f\u041e \u043f\u0440\u043e\u0433\u0440\u0430\u043c\u043c\u043d\u043e-\u0430\u043f\u043f\u0430\u0440\u0430\u0442\u043d\u043e\u0433\u043e \u0441\u0440\u0435\u0434\u0441\u0442\u0432\u0430",
  "\u0422\u0438\u043f \u043e\u0448\u0438\u0431\u043a\u0438 CWE": "CWE-404",
  "\u0423\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 \u0443\u044f\u0437\u0432\u0438\u043c\u043e\u0441\u0442\u0438": "\u0421\u0440\u0435\u0434\u043d\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 2.0 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 6,8)\n\u0412\u044b\u0441\u043e\u043a\u0438\u0439 \u0443\u0440\u043e\u0432\u0435\u043d\u044c \u043e\u043f\u0430\u0441\u043d\u043e\u0441\u0442\u0438 (\u0431\u0430\u0437\u043e\u0432\u0430\u044f \u043e\u0446\u0435\u043d\u043a\u0430 CVSS 3.1 \u0441\u043e\u0441\u0442\u0430\u0432\u043b\u044f\u0435\u0442 7,7)"
}

CVE-2025-20127 (GCVE-0-2025-20127)

Vulnerability from cvelistv5 – Published: 2025-08-14 16:28 – Updated: 2025-09-03 17:39

Title

Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software for Firepower 3100 and 4200 Series TLS Cipher Denial of Service Vulnerability

Summary

A vulnerability in the TLS 1.3 implementation for a specific cipher for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software for Cisco Firepower 3100 and 4200 Series devices could allow an authenticated, remote attacker to consume resources that are associated with incoming TLS 1.3 connections, which eventually could cause the device to stop accepting any new SSL/TLS or VPN requests. This vulnerability is due to the implementation of the TLS 1.3 Cipher TLS_CHACHA20_POLY1305_SHA256. An attacker could exploit this vulnerability by sending a large number of TLS 1.3 connections with the specific TLS 1.3 Cipher TLS_CHACHA20_POLY1305_SHA256. A successful exploit could allow the attacker to cause a denial of service (DoS) condition where no new incoming encrypted connections are accepted. The device must be reloaded to clear this condition. Note: These incoming TLS 1.3 connections include both data traffic and user-management traffic. After the device is in the vulnerable state, no new encrypted connections can be accepted.

Severity

7.7 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2025-08-14 18:41 UTC

CWE

CWE-404 - Improper Resource Shutdown or Release

Assigner

cisco mitre root Scorecard

References

1 reference

URL	Tags
https://sec.cloudapps.cisco.com/security/center/c…

Impacted products

2 products

Vendor	Product	Version
Cisco	Cisco Adaptive Security Appliance (ASA) Software	Affected: 9.20.1 Affected: 9.20.1.5 Affected: 9.20.2 Affected: 9.20.2.10 Affected: 9.20.2.21 Affected: 9.20.2.22 Affected: 9.20.3 Affected: 9.22.1.1 Affected: 9.20.3.4 Affected: 9.20.3.7
Cisco	Cisco Firepower Threat Defense Software	Affected: 7.4.0 Affected: 7.4.1 Affected: 7.4.1.1 Affected: 7.4.2 Affected: 7.6.0 Affected: 7.4.2.1

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2025-20127",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2025-08-14T18:41:43.684080Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2025-08-14T19:21:36.390Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unknown",
          "product": "Cisco Adaptive Security Appliance (ASA) Software",
          "vendor": "Cisco",
          "versions": [
            {
              "status": "affected",
              "version": "9.20.1"
            },
            {
              "status": "affected",
              "version": "9.20.1.5"
            },
            {
              "status": "affected",
              "version": "9.20.2"
            },
            {
              "status": "affected",
              "version": "9.20.2.10"
            },
            {
              "status": "affected",
              "version": "9.20.2.21"
            },
            {
              "status": "affected",
              "version": "9.20.2.22"
            },
            {
              "status": "affected",
              "version": "9.20.3"
            },
            {
              "status": "affected",
              "version": "9.22.1.1"
            },
            {
              "status": "affected",
              "version": "9.20.3.4"
            },
            {
              "status": "affected",
              "version": "9.20.3.7"
            }
          ]
        },
        {
          "defaultStatus": "unknown",
          "product": "Cisco Firepower Threat Defense Software",
          "vendor": "Cisco",
          "versions": [
            {
              "status": "affected",
              "version": "7.4.0"
            },
            {
              "status": "affected",
              "version": "7.4.1"
            },
            {
              "status": "affected",
              "version": "7.4.1.1"
            },
            {
              "status": "affected",
              "version": "7.4.2"
            },
            {
              "status": "affected",
              "version": "7.6.0"
            },
            {
              "status": "affected",
              "version": "7.4.2.1"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "A vulnerability in the TLS 1.3 implementation for a specific cipher for Cisco Secure Firewall Adaptive Security Appliance (ASA) Software and Cisco Secure Firewall Threat Defense (FTD) Software for Cisco Firepower 3100 and 4200 Series devices could allow an authenticated, remote attacker to consume resources that are associated with incoming TLS 1.3 connections, which eventually could cause the device to stop accepting any new SSL/TLS or VPN requests.\r\n\r\nThis vulnerability is due to the implementation of the TLS 1.3 Cipher TLS_CHACHA20_POLY1305_SHA256. An attacker could exploit this vulnerability by sending a large number of TLS 1.3 connections with the specific TLS 1.3 Cipher TLS_CHACHA20_POLY1305_SHA256. A successful exploit could allow the attacker to cause a denial of service (DoS) condition where no new incoming encrypted connections are accepted. The device must be reloaded to clear this condition.\r\nNote: These incoming TLS 1.3 connections include both data traffic and user-management traffic. After the device is in the vulnerable state, no new encrypted connections can be accepted."
        }
      ],
      "exploits": [
        {
          "lang": "en",
          "value": "The Cisco Product Security Incident Response Team (PSIRT) is not aware of any public announcements or malicious use of the vulnerability that is described in this advisory."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
            "availabilityImpact": "HIGH",
            "baseScore": 7.7,
            "baseSeverity": "HIGH",
            "confidentialityImpact": "NONE",
            "integrityImpact": "NONE",
            "privilegesRequired": "LOW",
            "scope": "CHANGED",
            "userInteraction": "NONE",
            "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H",
            "version": "3.1"
          },
          "format": "cvssV3_1"
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-404",
              "description": "Improper Resource Shutdown or Release",
              "lang": "en",
              "type": "cwe"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2025-09-03T17:39:26.506Z",
        "orgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
        "shortName": "cisco"
      },
      "references": [
        {
          "name": "cisco-sa-3100_4200_tlsdos-2yNSCd54",
          "url": "https://sec.cloudapps.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-3100_4200_tlsdos-2yNSCd54"
        }
      ],
      "source": {
        "advisory": "cisco-sa-3100_4200_tlsdos-2yNSCd54",
        "defects": [
          "CSCwm91176"
        ],
        "discovery": "EXTERNAL"
      },
      "title": "Cisco Adaptive Security Appliance Software and Firepower Threat Defense Software for Firepower 3100 and 4200 Series TLS Cipher Denial of Service Vulnerability"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "d1c1063e-7a18-46af-9102-31f8928bc633",
    "assignerShortName": "cisco",
    "cveId": "CVE-2025-20127",
    "datePublished": "2025-08-14T16:28:07.785Z",
    "dateReserved": "2024-10-10T19:15:13.212Z",
    "dateUpdated": "2025-09-03T17:39:26.506Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.1"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

Related by attack behaviour

Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

Action not permitted

BDU:2025-10339 (CVE-2025-20127)

CVE-2025-20127 (GCVE-0-2025-20127)

Tags

Sightings

Nomenclature

Related by attack behaviour