CVE-2024-38621

Description

In the Linux kernel, the following vulnerability has been resolved: media: stk1160: fix bounds checking in stk1160_copy_video() The subtract in this condition is reversed. The ->length is the length of the buffer. The ->bytesused is how many bytes we have copied thus far. When the condition is reversed that means the result of the subtraction is always negative but since it's unsigned then the result is a very high positive value. That means the overflow check is never true. Additionally, the ->bytesused doesn't actually work for this purpose because we're not writing to "buf->mem + buf->bytesused". Instead, the math to calculate the destination where we are writing is a bit involved. You calculate the number of full lines already written, multiply by two, skip a line if necessary so that we start on an odd numbered line, and add the offset into the line. To fix this buffer overflow, just take the actual destination where we are writing, if the offset is already out of bounds print an error and return. Otherwise, write up to buf->length bytes.

Gravité et risque d'exploitation

CVE-2024-38621 obtient un score CVSS de 0.0/10, soit une gravité non évaluée. Selon le modèle EPSS, la probabilité qu'elle soit exploitée dans les 30 prochains jours est de 0.28 %, ce qui la place devant 19.0 % des CVE référencées.

Que faire ?

• Vérifiez si Linux (versions <=6.1.*, 6.9.4, 6.10, <f6a392266276730bea893b55d12940e32a25f56a, 0, <b504518a397059e1d55c521ba0ea2b545a6c4b52, <d410017a7181cb55e4a5c810b32b75e4416c6808, <ecf4ddc3aee8ade504c4d36b7b4053ce6093e200, <=5.10.*, <=6.6.*, <=6.9.*, 5.10.219, 4.19.316, <=5.4.*, 6.6.33, <7532bcec0797adfa08791301c3bcae14141db3bd, <=4.19.*, 5.4.278, 5.15.161, <a08492832cc4cacc24e0612f483c86ca899b9261, <3.7, 9cb2173e6ea8f2948bd1367c93083a2500fcf08f, 6.1.93, <=*, 3.7, <=5.15.*, <faa4364bef2ec0060de381ff028d1d836600a381, <a16775828aaed1c54ff4e6fe83e8e4d5c6a50cb7) est présent sur votre parc.
• Appliquez le correctif ou la version corrigée indiqués dans les références de l'éditeur.
• À défaut de correctif, limitez l'exposition (filtrage réseau, désactivation du composant).
• Automatisez la détection : les agents CVE Heimdall (gratuits, open source) corrèlent l'inventaire de vos serveurs avec la base CVE.

Références

• https://git.kernel.org/stable/c/f6a392266276730bea893b55d12940e32a25f56a
• https://git.kernel.org/stable/c/ecf4ddc3aee8ade504c4d36b7b4053ce6093e200
• https://git.kernel.org/stable/c/a16775828aaed1c54ff4e6fe83e8e4d5c6a50cb7
• https://git.kernel.org/stable/c/7532bcec0797adfa08791301c3bcae14141db3bd
• https://git.kernel.org/stable/c/b504518a397059e1d55c521ba0ea2b545a6c4b52
• https://git.kernel.org/stable/c/d410017a7181cb55e4a5c810b32b75e4416c6808
• https://git.kernel.org/stable/c/a08492832cc4cacc24e0612f483c86ca899b9261
• https://git.kernel.org/stable/c/faa4364bef2ec0060de381ff028d1d836600a381