Skip to main content
veriom
Menu

Explore Veriom products, resources, and account pages.

CVE-2021-22893Ivanti Pulse Connect Secure Use-After-Free Vulnerability

Patch nowCritical10.0Exploited, CISA due date 2022-05-03EPSS 48%, higher than 99% of scored CVEs

CVE-2021-22893 is a use after free in Ivanti Pulse Connect Secure, rated critical (10.0 on CVSS 3.1).

Why this priority: Exploited in the wild: listed in CISA's KEV catalog.

Published · Updated · NVD status: Analyzed

What it is

Code keeps using memory after releasing it, so an attacker who refills that memory can steer execution. The software does not prove who a caller is, so an attacker can pass as someone else.

How it is reached

An attacker can exploit it over the network, without an account, and nobody has to click anything.

What an attacker gains

A successful attack can read the data it protects, change data or behaviour and take it offline. In practice, this kind of flaw lets an attacker crash the process, read memory, or in the worst case run code. The damage can spread past the vulnerable component into others.

Is it being exploited?

CISA added it to the Known Exploited Vulnerabilities catalog on 2021-11-03: it is being exploited in the wild. CISA links it to ransomware campaigns. It can be exploited automatically, at scale. EPSS estimates a 48% chance of exploitation activity in the next 30 days, higher than 99% of scored CVEs.

What to do

  1. Treat it as urgent: it is on CISA's KEV list. CISA's deadline for US federal agencies: 2022-05-03.
  2. No fixed version is listed yet. Find every place Ivanti Pulse Connect Secure runs, watch the references for a fix, and plan a replacement if it is no longer supported.
  3. While there is no fix, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
  4. Check exposed instances for signs of compromise, not only for the version.

Description from NVD

Pulse Connect Secure 9.0R3/9.1R1 and higher is vulnerable to an authentication bypass vulnerability exposed by the Windows File Share Browser and Pulse Secure Collaboration features of Pulse Connect Secure that can allow an unauthenticated user to perform remote arbitrary code execution on the Pulse Connect Secure gateway. This vulnerability has been exploited in the wild.

What this means for your architecture.

A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.

Components it touches

  • Network edge devices: VPNs, firewalls, routers and gateways. They sit between the internet and internal networks, so a flaw in one is often the first step into everything behind it.
  • Native code: operating systems, browsers and firmware. The flaw sits wherever native code reads untrusted data.
  • Network appliances and media or file parsers. The flaw sits wherever native code reads untrusted data.
  • Sign-in, session and token handling. The flaw sits between anonymous callers and authenticated sessions.

Trust boundaries in play

  • Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
  • Isolation between components. The impact crosses out of the vulnerable component into others it should be isolated from.
  • Wherever native code reads untrusted data. An attacker who crosses it can crash the process, read memory, or in the worst case run code.
  • Between anonymous callers and authenticated sessions. An attacker who crosses it can act as a signed-in user, or an administrator, without valid credentials.

Questions to answer about your own systems

  • Where does Ivanti Pulse Connect Secure run in your systems, and at which version?
  • Which of those instances can be reached from the internet or partner networks?
  • What can it reach once compromised: which data stores, secrets and services?
See how Veriom maps an architectureTake the interactive tour

Read more

Sources

  • CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
  • Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
  • Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
  • Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.