CVE-2024-35884
Linux Kernel UDP GSO Tunneling Vulnerability
Description
In the Linux kernel, the following vulnerability has been resolved: udp: do not accept non-tunnel GSO skbs landing in a tunnel When rx-udp-gro-forwarding is enabled UDP packets might be GROed when being forwarded. If such packets might land in a tunnel this can cause various issues and udp_gro_receive makes sure this isn't the case by looking for a matching socket. This is performed in udp4/6_gro_lookup_skb but only in the current netns. This is an issue with tunneled packets when the endpoint is in another netns. In such cases the packets will be GROed at the UDP level, which leads to various issues later on. The same thing can happen with rx-gro-list. We saw this with geneve packets being GROed at the UDP level. In such case gso_size is set; later the packet goes through the geneve rx path, the geneve header is pulled, the offset are adjusted and frag_list skbs are not adjusted with regard to geneve. When those skbs hit skb_fragment, it will misbehave. Different outcomes are possible depending on what the GROed skbs look like; from corrupted packets to kernel crashes. One example is a BUG_ON[1] triggered in skb_segment while processing the frag_list. Because gso_size is wrong (geneve header was pulled) skb_segment thinks there is "geneve header size" of data in frag_list, although it's in fact the next packet. The BUG_ON itself has nothing to do with the issue. This is only one of the potential issues. Looking up for a matching socket in udp_gro_receive is fragile: the lookup could be extended to all netns (not speaking about performances) but nothing prevents those packets from being modified in between and we could still not find a matching socket. It's OK to keep the current logic there as it should cover most cases but we also need to make sure we handle tunnel packets being GROed too early. This is done by extending the checks in udp_unexpected_gso: GSO packets lacking the SKB_GSO_UDP_TUNNEL/_CSUM bits and landing in a tunnel must be segmented. [1] kernel BUG at net/core/skbuff.c:4408! RIP: 0010:skb_segment+0xd2a/0xf70 __udp_gso_segment+0xaa/0x560
INFO
Published Date :
May 19, 2024, 9:15 a.m.
Last Modified :
Nov. 21, 2024, 9:21 a.m.
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
Remotely Exploitable :
Yes !
Impact Score :
5.9
Exploitability Score :
2.8
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2024-35884
.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2024-35884
vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2024-35884
vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
CVE Modified by af854a3a-2127-422b-91ae-364da2661108
Nov. 21, 2024
Action Type Old Value New Value Added Reference https://git.kernel.org/stable/c/3001e7aa43d6691db2a878b0745b854bf12ddd19 Added Reference https://git.kernel.org/stable/c/3391b157780bbedf8ef9f202cbf10ee90bf6b0f8 Added Reference https://git.kernel.org/stable/c/35fe0e0b5c00bef7dde74842a2564c43856fbce4 Added Reference https://git.kernel.org/stable/c/3d010c8031e39f5fa1e8b13ada77e0321091011f Added Reference https://git.kernel.org/stable/c/d12245080cb259d82b34699f6cd4ec11bdb688bd Added Reference https://git.kernel.org/stable/c/d49ae15a5767d4e9ef8bbb79e42df1bfebc94670 Added Reference https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Nov. 13, 2024
Action Type Old Value New Value Added CVSS V3.1 CISA-ADP AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Nov. 05, 2024
Action Type Old Value New Value Removed Reference kernel.org https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jun. 25, 2024
Action Type Old Value New Value Added Reference kernel.org https://lists.debian.org/debian-lts-announce/2024/06/msg00017.html [No types assigned] -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 29, 2024
Action Type Old Value New Value -
CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
May. 19, 2024
Action Type Old Value New Value Added Description In the Linux kernel, the following vulnerability has been resolved: udp: do not accept non-tunnel GSO skbs landing in a tunnel When rx-udp-gro-forwarding is enabled UDP packets might be GROed when being forwarded. If such packets might land in a tunnel this can cause various issues and udp_gro_receive makes sure this isn't the case by looking for a matching socket. This is performed in udp4/6_gro_lookup_skb but only in the current netns. This is an issue with tunneled packets when the endpoint is in another netns. In such cases the packets will be GROed at the UDP level, which leads to various issues later on. The same thing can happen with rx-gro-list. We saw this with geneve packets being GROed at the UDP level. In such case gso_size is set; later the packet goes through the geneve rx path, the geneve header is pulled, the offset are adjusted and frag_list skbs are not adjusted with regard to geneve. When those skbs hit skb_fragment, it will misbehave. Different outcomes are possible depending on what the GROed skbs look like; from corrupted packets to kernel crashes. One example is a BUG_ON[1] triggered in skb_segment while processing the frag_list. Because gso_size is wrong (geneve header was pulled) skb_segment thinks there is "geneve header size" of data in frag_list, although it's in fact the next packet. The BUG_ON itself has nothing to do with the issue. This is only one of the potential issues. Looking up for a matching socket in udp_gro_receive is fragile: the lookup could be extended to all netns (not speaking about performances) but nothing prevents those packets from being modified in between and we could still not find a matching socket. It's OK to keep the current logic there as it should cover most cases but we also need to make sure we handle tunnel packets being GROed too early. This is done by extending the checks in udp_unexpected_gso: GSO packets lacking the SKB_GSO_UDP_TUNNEL/_CSUM bits and landing in a tunnel must be segmented. [1] kernel BUG at net/core/skbuff.c:4408! RIP: 0010:skb_segment+0xd2a/0xf70 __udp_gso_segment+0xaa/0x560 Added Reference kernel.org https://git.kernel.org/stable/c/3391b157780bbedf8ef9f202cbf10ee90bf6b0f8 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/d49ae15a5767d4e9ef8bbb79e42df1bfebc94670 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/d12245080cb259d82b34699f6cd4ec11bdb688bd [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/3001e7aa43d6691db2a878b0745b854bf12ddd19 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/35fe0e0b5c00bef7dde74842a2564c43856fbce4 [No types assigned] Added Reference kernel.org https://git.kernel.org/stable/c/3d010c8031e39f5fa1e8b13ada77e0321091011f [No types assigned]
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2024-35884
is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2024-35884
weaknesses.