Vulnerability record · CVE-2012-3523 · published 11 November 2012
CVE-2012-3523: Isc inn permissions and access controls vulnerability
Isc · Inn
The STARTTLS implementation in nnrpd in INN before 2.5.3 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.
Description
The STARTTLS implementation in nnrpd in INN before 2.5.3 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.
AV:N/AC:M/Au:N/C:P/I:P/A:P
Affected products
1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.
References
Track CVE-2012-3523 inside VULONE
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Related vulnerabilities
Same products first, then exploited flaws of the same weakness class.
Source: NIST National Vulnerability Database (record CVE-2012-3523), CISA KEV, FIRST EPSS (scores of 2026-09-30). This page is refreshed as NVD updates the record.
