Microsoft Exchange Server 5.5 and 5.0 does not properly handle (1) malformed NNTP data, or (2) malformed SMTP data, which allows remote att…

published 1999-12-31 26y ago modified 2026-06-16 4mo ago also EUVD-1999-1024

cvss: 5.0; version 2.0, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 13.2%; EPSS 13.2% chance of exploitation in 30 days, percentile 96%
public exploits: 0; none known

Microsoft Exchange Server 5.5 and 5.0 does not properly handle (1) malformed NNTP data, or (2) malformed SMTP data, which allows remote attackers to cause a denial of service (application error).

Patch / fix

links 1

docs.microsoft.com/en-us/security-updates/securitybulletins/1998/ms98-007 advisory

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Exploit prediction

13.23% chance of exploitation in the next 30 days, higher than 96% of all scored CVEs (FIRST EPSS, 2026-11-14).

CVSS scores

assigned by	version	score	vector
NVD	2.0	5.0	AV:N/AC:L/Au:N/C:N/I:N/A:P

Classification

Technology feeds

Microsoft Exchange rss critical rss

References

docs.microsoft.com /en-us/security-updates/securitybulletins/1998/ms98-007
vendor-advisory, patch

Sources

CVE List CVE-1999-1043
NVD CVE-1999-1043

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