CVE-2003-0795
CWE-20Published: December 15, 2003· Updated: Jun 16, 2026
Official Description
The vty layer in Quagga before 0.96.4, and Zebra 0.93b and earlier, does not verify that sub-negotiation is taking place when processing the SE marker, which allows remote attackers to cause a denial of service (crash) via a malformed telnet command to the telnet CLI port, which may trigger a null dereference.
Technical Analysis
CVE-2003-0795 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
Exploitation requires some privileges, which limits the exposure to scenarios where an attacker has already gained initial access.
A proof-of-concept (PoC) exploit exists for CVE-2003-0795. While not yet confirmed in active campaigns, the availability of PoC code increases exploitation risk substantially.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (10)
Quick Facts
Related CVEs (CWE-20)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2003-0795 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts