Cisco StarOS for Cisco ASR 5000 Series Routers Arbitrary File Read Vulnerability

published 2021-01-13 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-6612

cvss: 6.5; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 70%
public exploits: 0; none known

A vulnerability in the Secure FTP (SFTP) of Cisco StarOS for Cisco ASR 5000 Series Routers could allow an authenticated, remote attacker to read arbitrary files on an affected device. To exploit this vulnerability, the attacker would need to have valid credentials on the affected device. The vulnerability is due to insecure handling of symbolic links. An attacker could exploit this vulnerability by sending a crafted SFTP command to an affected device. A successful exploit could allow the attacker to read arbitrary files on the affected device.

Patch / fix

fixed in 1

cisco staros 21.19.7

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: partial
Assessed: 2 y ago (2024-11-08)

Exploit prediction

1.29% chance of exploitation in the next 30 days, higher than 70% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD	3.1	6.5	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N
NVD	2.0	4.0	AV:N/AC:L/Au:S/C:P/I:N/A:N

Affected products

Cisco Cisco ASR 5000 Series Software

Classification

Weakness

CWE-61 UNIX Symbolic Link (Symlink) Following
CWE-59 Improper Link Resolution Before File Access

References

tools.cisco.com /security/center/content/CiscoSecurityAdvisory/cisco-sa-staros-file-read-L3RDvtey
vendor-advisory

Sources

CVE List CVE-2021-1145
NVD CVE-2021-1145

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Summary