CVE-2009-4921
CVE-2009-4921 is a high-severity vulnerability in Cisco Asa 5580 with a CVSS 2.0 base score of 7.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.
Key facts
- Severity: High (CVSS 2.0 base score 7.8)
- EPSS exploit prediction: 1% (65th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-20
- Affected product: Cisco Asa 5580
- Published:
- Last modified:
Description
Cisco Adaptive Security Appliances (ASA) 5580 series devices with software before 8.1(2) allow remote attackers to cause a denial of service (traceback) via malformed TCP packets, aka Bug ID CSCsm84110.
Frequently asked questions
- What is CVE-2009-4921?
- Cisco Adaptive Security Appliances (ASA) 5580 series devices with software before 8.1(2) allow remote attackers to cause a denial of service (traceback) via malformed TCP packets, aka Bug ID CSCsm84110.
- How severe is CVE-2009-4921?
- CVE-2009-4921 has a CVSS 2.0 base score of 7.8, rated high severity.
- Is CVE-2009-4921 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2009-4921?
- CVE-2009-4921 affects Cisco Asa 5580. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2009-4921?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2009-4921 published?
- CVE-2009-4921 was published on 2010-06-29 and last updated on 2026-06-16.
References
Affected products (1)
- cpe:2.3:h:cisco:asa_5580:*:*:*:*:*:*:*:*
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