CVE-2024-47678 icmp: change the order of rate limits
Attackers can exploit ICMP rate limiting order to perform side-channel attacks, potentially disclosing sensitive information.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-47678?
CVE-2024-47678 is a critical vulnerability in Linux kernel, published on 21 Oct 2024. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
icmp: change the order of rate limits
ICMP messages are ratelimited :
After the blamed commits, the two rate limiters are applied in this order:
1) host wide ratelimit (icmp_global_allow())
2) Per destination ratelimit (inetpeer based)
In order to avoid side-channels attacks, we need to apply the per destination check first.
This patch makes the following change :
1) icmp_global_allow() checks if the host wide limit is reached. But credits are not yet consumed. This is deferred to 3)
2) The per destination limit is checked/updated. This might add a new node in inetpeer tree.
3) icmp_global_consume() consumes tokens if prior operations succeeded.
This means that host wide ratelimit is still effective in keeping inetpeer tree small even under DDOS.
As a bonus, I removed icmp_global.lock as the fast path can use a lock-free operation.
Weakness: CWE-203
Which versions are affected by CVE-2024-47678?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2024-47678?
Apply the vendor's patch.
Is CVE-2024-47678 being exploited?
There is no known exploitation of CVE-2024-47678 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as AZL-50716, AZL-50979, BELL-CVE-2024-47678, DEBIAN-CVE-2024-47678, GHSA-522v-vw33-wcv7, ROOT-OS-DEBIAN-11-CVE-2024-47678 and 2 more.