Directory traversal vulnerability in Cisco AnyConnect Secure Mobility Client 4.0(2049) allows remote head-end systems to write to arbitrary

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

• cisco anyconnect secure mobility client4.0(2049)

Other highest-scoring records for the same primary product.

• CVE-2020-3433Cisco AnyConnect Secure Mobility Client for Windows DLL Hijacking VulnerabilityKEV
  64This week
• CVE-2020-3153Cisco AnyConnect Secure Mobility Client for Windows Uncontrolled Search Path VulnerabilityKEV
  64This week
• CVE-2011-2039The helper application in Cisco AnyConnect Secure Mobility Client (formerly AnyConnect VPN Client) before 2.3.185 on Windows, and on Windows
  51Plan
• CVE-2011-2040The helper application in Cisco AnyConnect Secure Mobility Client (formerly AnyConnect VPN Client) before 2.5.3041, and 3.0.x before 3.0.629
  40Plan
• CVE-2012-3088Cisco AnyConnect Secure Mobility Client 3.1.x before 3.1.00495, and 3.2.x, does not check whether an HTTP request originally contains ScanSa
  38Monitor
• CVE-2012-2493The VPN downloader implementation in the WebLaunch feature in Cisco AnyConnect Secure Mobility Client 2.x before 2.5 MR6 on Windows, and 2.x
  38Monitor

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Root cause

A user-supplied file name is joined with the allowed directory, but the result is never checked to confirm it is still inside that directory.

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

1const file = path.join(ROOT, req.query.name);2res.sendFile(file);

1const file = path.resolve(ROOT, req.query.name);2if (!file.startsWith(ROOT + path.sep)) {3  return res.sendStatus(400);4}5res.sendFile(file);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.