CVE-2023-53559: linux kernel Use-After-Free — Fix

Description

In the Linux kernel, the following vulnerability has been resolved: ip_vti: fix potential slab-use-after-free in decode_session6 When ip_vti device is set to the qdisc of the sfb type, the cb field of the sent skb may be modified during enqueuing. Then, slab-use-after-free may occur when ip_vti device sends IPv6 packets. As commit f855691975bb ("xfrm6: Fix the nexthdr offset in _decode_session6.") showed, xfrm_decode_session was originally intended only for the receive path. IP6CB(skb)->nhoff is not set during transmission. Therefore, set the cb field in the skb to 0 before sending packets.

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CVSS v3.1 Score

7.8

HIGH

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-416 Use After Free

Affected Products

Vendor	Product	Versions
linux	linux_kernel	3.19.1 — 4.14.324
linux	linux_kernel	4.15 — 4.19.293
linux	linux_kernel	4.20 — 5.4.255
linux	linux_kernel	5.5 — 5.10.192
linux	linux_kernel	5.11 — 5.15.128
linux	linux_kernel	5.16 — 6.1.47
linux	linux_kernel	6.2 — 6.4.12
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All
linux	linux_kernel	All

References

Advisories & Patches

https://git.kernel.org/stable/c/0b4d69539fdea138af2befe08893850c89248068 https://git.kernel.org/stable/c/2b05bf5dc437f7891dd409a3eaf5058459391c7a https://git.kernel.org/stable/c/6018a266279b1a75143c7c0804dd08a5fc4c3e0b https://git.kernel.org/stable/c/78e397a43e1c47321a4679cc49a6c4530bf820b9 https://git.kernel.org/stable/c/7dfe23659f3677c08a60a0056cda2d91a79c15ca https://git.kernel.org/stable/c/82fb41c5de243e7dfa90f32ca58e35adaff56c1d https://git.kernel.org/stable/c/d34c30442d5e53a33cde79ca163320dbe2432cbd https://git.kernel.org/stable/c/e1e04cc2ef2c0c0866c19f5627149a76c2baae32

Frequently Asked Questions

What is CVE-2023-53559? +

In the Linux kernel, the following vulnerability has been resolved: ip_vti: fix potential slab-use-after-free in decode_session6 When ip_vti device is set to the qdisc of the sfb type, the cb field of the sent skb may be modified during enqueuing. Then, slab-use-after-free may occur when ip_vti device sends IPv6 packets. As commit f855691975bb ("xfrm6: Fix the nexthdr offset in _decode_session6.") showed, xfrm_decode_session was originally intended only for the receive path. IP6CB(skb)->nhoff is not set during transmission. Therefore, set the cb field in the skb to 0 before sending packets. It has a CVSS v3.1 base score of 7.8 (HIGH).

How severe is CVE-2023-53559? +

CVE-2023-53559 has a CVSS v3.1 score of 7.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

What products are affected by CVE-2023-53559? +

CVE-2023-53559 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.

How do I check if I'm vulnerable to CVE-2023-53559? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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