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CVE-1999-0284

33
FAUCET Score

CVE-1999-0284 describes a critical buffer overflow vulnerability in the SMTP HELO command, impacting various NT mail servers including Microsoft Exchange, IBM Lotus Domino, and Ipswitch Imail. This flaw allows an unauthenticated attacker to trigger a denial of service, and potentially execute arbitrary code, due to a high-severity CVSS score of 7.5. While not currently on CISA's KEV catalog, public exploit code exists for MDaemon, Ipswitch Imail, and Microsoft Exchange 4.0/5.0, indicating a clear path for exploitation despite minimal community discussion or media coverage.

Impacted Technologies

VendorProductVersion(s)CPE
All Versions ImpactedCPE matchmatch criteria
cpe:2.3:a:ibm:lotus_domino_mail_server:*:*:*:*:*:*:*:*
4.0CPE matchmatch criteria
cpe:2.3:a:microsoft:exchange_server:4.0:-:*:*:*:*:*:*
5.0CPE matchmatch criteria
cpe:2.3:a:microsoft:exchange_server:5.0:-:*:*:*:*:*:*

CVSS Data

CVSS version used by this source: 2.0

7.5HIGH

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

Confidentiality Impact
PARTIAL
Integrity Impact
PARTIAL
Availability Impact
PARTIAL
Access Vector
NETWORK
Access Complexity
LOW
Authentication
NONE
Exploitability Score
10.0
Impact Score
6.4
CvssVersion
2.0

Exploit Intelligence

EPSS Score
11.63%
Probability of exploitation in next 30 days
EPSS Percentile
95.6%
Percentile rank of EPSS score among Peer Group
As of 2026-07-28
Model: v2026.06.15
ExploitDB: EDB-23146 · Mar 10, 1999
This CVE's current EPSS score of 0.1163 is in the 93rd percentile among its peer group of 51,553 CVEs.

Social Chatter

No social media mentions found for this CVE.

The average CVE in this peer group has 0.0 Twitter, 0.0 Reddit, 0.1 Bluesky, 0.1 Mastodon, and 0.4 GitHub mentions.

Media Mentions

No media coverage found for this CVE.

The average CVE in this peer group has 0.1 InfoSec Media, 0.0 Vendor Blog, and 0.0 Security Researcher mentions.

Remediation

Remediation records are not available for this CVE.

References

exchange.xforce.ibmcloud.com / vulnerabilities/CVE-1999-0284