Skip to main content

CVE-2026-121353Adobe Connect CRLF injection

High priorityCritical10.0EPSS not scored yet

CVE-2026-121353 is a CRLF injection in Adobe Connect, rated critical (10.0 on CVSS 3.1).

Why this priority: Critical, and reachable over the network without an account.

Published · Updated · NVD status: Received

What it is

Line breaks in input end up in headers or logs, letting an attacker add lines of their own.

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 and change data or behaviour. In practice, this kind of flaw lets an attacker smuggle requests past the proxy's checks. The damage can spread past the vulnerable component into others.

Is it being exploited?

There is no public report of exploitation yet.

What to do

  1. Upgrade Adobe Connect to a fixed version for your release line (12.8.a, 12.9.a, 12.10.f).
  2. Until it is patched, keep it off the internet or behind a VPN, allowlist or authenticating proxy.

Description from NVD

Adobe Connect is affected by an Improper Neutralization of CRLF Sequences ('CRLF Injection') vulnerability that could result in arbitrary code execution in the context of the current user, potentially gaining elevated access or control over the victim's account or session. Exploitation of this issue does not require user interaction. Scope is changed.

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

  • Proxies, load balancers and the servers behind them. The flaw sits between a front-end proxy and its back end.

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.
  • Between a front-end proxy and its back end. An attacker who crosses it can smuggle requests past the proxy's checks.

Questions to answer about your own systems

  • Where does Adobe Connect 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?

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.