CVE-2009-4893
CVE-2009-4893 is a medium-severity vulnerability in Unrealircd with a CVSS 2.0 base score of 6.8. 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-119.
Key facts
- Severity: Medium (CVSS 2.0 base score 6.8)
- EPSS exploit prediction: 3% (83rd percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-119
- Affected product: Unrealircd
- Published:
- Last modified:
Description
Buffer overflow in UnrealIRCd 3.2beta11 through 3.2.8, when allow::options::noident is enabled, allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via unspecified vectors.
Frequently asked questions
- What is CVE-2009-4893?
- Buffer overflow in UnrealIRCd 3.2beta11 through 3.2.8, when allow::options::noident is enabled, allows remote attackers to cause a denial of service (crash) and possibly execute arbitrary code via unspecified vectors.
- How severe is CVE-2009-4893?
- CVE-2009-4893 has a CVSS 2.0 base score of 6.8, rated medium severity.
- Is CVE-2009-4893 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 3% (83rd percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2009-4893?
- CVE-2009-4893 primarily affects Unrealircd. In total, 31 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2009-4893?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2009-4893 published?
- CVE-2009-4893 was published on 2010-06-15 and last updated on 2026-06-16.
References
- http://security.gentoo.org/glsa/glsa-201006-21.xml
- http://www.openwall.com/lists/oss-security/2010/06/14/13
- http://www.securityfocus.com/bid/42077
- http://www.unrealircd.com/txt/unrealsecadvisory.20090413.txt
Affected products (31)
- cpe:2.3:a:unrealircd:unrealircd:3.2:beta11:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.1:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.1:pre1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.1:pre2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.2:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.2:pre1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.3:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.3:pre1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.3:pre2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.3:pre3:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.3:pre4:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.4:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.4:pre1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.4:pre2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.4:rc1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.4:rc2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.4:rc3:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.5:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.5:rc1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.5:rc2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.5:rc3:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.6:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.6:rc1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.6:rc2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.6:rc3:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.7:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.7:rc1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.7:rc2:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.8:*:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.8:rc1:*:*:*:*:*:*
- cpe:2.3:a:unrealircd:unrealircd:3.2.8:rc2:*:*:*:*:*:*
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