CVE-2024-35894: mptcp: prevent BPF accessing lowat from a subflow socket.
Vulnerability summary
CVE-2024-35894 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 12.8% of scored vulnerabilities.
Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 5 · Related 4Timeline
- 19-05-2024PublishedVulnerability first disclosed.
- 05-08-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: mptcp: prevent BPF accessing lowat from a subflow socket. Alexei reported the following splat: WARNING: CPU: 32 PID: 3276 at net/mptcp/subflow.c:1430 subflow_data_ready+0x147/0x1c0 Modules linked in: dummy bpf_testmod(O) [last unloaded: bpf_test_no_cfi(O)] CPU: 32 PID: 3276 Comm: test_progs Tainted: GO 6.8.0-12873-g2c43c33bfd23 Call Trace: <TASK> mptcp_set_rcvlowat+0x79/0x1d0 sk_setsockopt+0x6c0/0x1540 __bpf_setsockopt+0x6f/0x90 bpf_sock_ops_setsockopt+0x3c/0x90 bpf_prog_509ce5db2c7f9981_bpf_test_sockopt_int+0xb4/0x11b bpf_prog_dce07e362d941d2b_bpf_test_socket_sockopt+0x12b/0x132 bpf_prog_348c9b5faaf10092_skops_sockopt+0x954/0xe86 __cgroup_bpf_run_filter_sock_ops+0xbc/0x250 tcp_connect+0x879/0x1160 tcp_v6_connect+0x50c/0x870 mptcp_connect+0x129/0x280 __inet_stream_connect+0xce/0x370 inet_stream_connect+0x36/0x50 bpf_trampoline_6442491565+0x49/0xef inet_stream_connect+0x5/0x50 __sys_connect+0x63/0x90 __x64_sys_connect+0x14/0x20 The root cause of the issue is that bpf allows accessing mptcp-level proto_ops from a tcp subflow scope. Fix the issue detecting the problematic call and preventing any action.
CVSS metrics
4 scores · 4 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- OSV · DebianEcosystem advisory · calculated7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- NVDNIST7.8HighCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
EPSS trend
Probability
0.22%
Chance of exploitation in the next 30 days
Percentile
13%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.22% on 04-10-2026
Known exploited
Compare KEV catalogsNot in the CISA KEV catalog.
Not in the ENISA CNW catalog.
Not in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeNo weakness data has been published for this record.
Affected systems
Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.
Ubuntu78 products
- linux< 6.8.0-38.38
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws< 6.8.0-1011.12
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
Linux2 products
- linux≥ 124a4885b55f3039c697feb53edc5ad88bf21161, < ee3c845787b621cfe82c2e52c513024a9d7a78f5 | ≥ 5684ab1a0effbfeb706f47d85785f653005b97b1, < 3ffb1ab698376f09cc33101c07c1be229389fe29 | ≥ 5684ab1a0effbfeb706f47d85785f653005b97b1, < fcf4692fa39e86a590c14a4af2de704e1d20a3b5 | 6.7
- linux_kernel≥ 6.7, < 6.8.5 | 6.9:rc1 | 6.9:rc2
Debian1 product
- linux< 6.8.9-1
3 vendors · 81 products