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Fencer Intel
medium 5.3

CVE-2021-1424 json

Cisco ASR 5000 Series Software (StarOS) ipsecmgr Process Denial of Service Vulnerability

published last yr. modified 4mo ago also EUVD-2021-6891

cvss
5.3
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 57%
public exploits
0
none known

Summary

A vulnerability in the ipsecmgr process of Cisco ASR 5000 Series Software (StarOS) could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition. This vulnerability is due to insufficient validation of incoming Internet Key Exchange Version 2 (IKEv2) packets. An attacker could exploit this vulnerability by sending specifically malformed IKEv2 packets to an affected device. A successful exploit could allow the attacker to cause the ipsecmgr process to restart, which would disrupt ongoing IKE negotiations and result in a temporary DoS condition.Cisco has released software updates that address this vulnerability. There are no workarounds that address this vulnerability.

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CISA SSVC

Exploitation
none
Automatable
yes
Technical impact
partial
Assessed
last yr.

Exploit prediction

0.81% chance of exploitation in the next 30 days, higher than 57% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by version score vector
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L/RL:X/RC:X/E:X
CNA 3.1 5.3 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

Affected products

  • Cisco Cisco ASR 5000 Series Software
  • cisco asr_5000_series_software

Classification

Weakness
  • CWE-119 Improper Restriction of Operations within the Bounds of a Memory Buffer

References

Sources

Fencer Intel keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.