CVE-2022-48906: mptcp: Correctly set DATA_FIN timeout when number of retransmits is large
Vulnerability summary
CVE-2022-48906 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 10.8% of scored vulnerabilities.
Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 3 · Related 3Timeline
- 22-08-2024PublishedVulnerability first disclosed.
- 23-05-2026Last modifiedVulnerability information updated.
Description
In the Linux kernel, the following vulnerability has been resolved: mptcp: Correctly set DATA_FIN timeout when number of retransmits is large Syzkaller with UBSAN uncovered a scenario where a large number of DATA_FIN retransmits caused a shift-out-of-bounds in the DATA_FIN timeout calculation: ================================================================================ UBSAN: shift-out-of-bounds in net/mptcp/protocol.c:470:29 shift exponent 32 is too large for 32-bit type 'unsigned int' CPU: 1 PID: 13059 Comm: kworker/1:0 Not tainted 5.17.0-rc2-00630-g5fbf21c90c60 #1 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.13.0-1ubuntu1.1 04/01/2014 Workqueue: events mptcp_worker Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106 ubsan_epilogue+0xb/0x5a lib/ubsan.c:151 __ubsan_handle_shift_out_of_bounds.cold+0xb2/0x20e lib/ubsan.c:330 mptcp_set_datafin_timeout net/mptcp/protocol.c:470 [inline] __mptcp_retrans.cold+0x72/0x77 net/mptcp/protocol.c:2445 mptcp_worker+0x58a/0xa70 net/mptcp/protocol.c:2528 process_one_work+0x9df/0x16d0 kernel/workqueue.c:2307 worker_thread+0x95/0xe10 kernel/workqueue.c:2454 kthread+0x2f4/0x3b0 kernel/kthread.c:377 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 </TASK> ================================================================================ This change limits the maximum timeout by limiting the size of the shift, which keeps all intermediate values in-bounds.
CVSS metrics
3 scores · 3 sources · 1 version- OSV · UbuntuEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- OSV · DebianEcosystem advisory · calculated5.5MediumCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.21%
Chance of exploitation in the next 30 days
Percentile
11%
Versus all other CVEs
30-day change
No change 0.00 pp
From 0.21% 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.
Ubuntu75 products
- linux-allwinner-5.19All versions (No fix recorded)
- linux-aws-5.0All versions (No fix recorded)
- linux-aws-5.11All versions (No fix recorded)
- linux-aws-5.13All versions (No fix recorded)
- linux-aws-5.19All versions (No fix recorded)
Linux2 products
- linux≥ 6477dd39e62c3a67cfa368ddc127410b4ae424c6, < 0c3f34beb459753f9f80d0cc14c1b50ab615c631 | ≥ 6477dd39e62c3a67cfa368ddc127410b4ae424c6, < 03ae283bd71f761feae3f402668d698b393b0e79 | ≥ 6477dd39e62c3a67cfa368ddc127410b4ae424c6, < 877d11f0332cd2160e19e3313e262754c321fa36 | 0af76111c2a6326e4bb56f64a6e453c6ec6dd2da | ≥ 5.12.4, < 5.13 | 5.13
- linux_kernel≥ 5.12.4, < 5.13 | ≥ 5.13, < 5.15.27 | ≥ 5.16, < 5.16.13 | 5.17:rc1 | 5.17:rc2 | 5.17:rc3 | 5.17:rc4 | 5.17:rc5 | 5.17:rc6
Debian1 product
- linux< 5.16.14-1
3 vendors · 78 products