CVE-2026-43252

MEDIUMNVD 5.55.5—
EchelonGraph scoreMEDIUM confidence

Score 5.5 from GitHub Security Advisory published 2026-05-06. NVD baseline CVSS 5.5; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.5EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.5Exploit: None knownExposed: 0

A fix is available — apply it.

In the Linux kernel, the following vulnerability has been resolved:

mptcp: pm: in-kernel: always set ID as avail when rm endp

Syzkaller managed to find a combination of actions that was generating this warning:

WARNING: net/mptcp/pm_kernel.c:1074 at __mark_subflow_endp_available net/mptcp/pm_kernel.c:1074 [inline], CPU#1: syz.7.48/2535 WARNING: net/mptcp/pm_kernel.c:1074 at mptcp_pm_nl_fullmesh net/mptcp/pm_kernel.c:1446 [inline], CPU#1: syz.7.48/2535 WARNING: net/mptcp/pm_kernel.c:1074 at mptcp_pm_nl_set_flags_all net/mptcp/pm_kernel.c:1474 [inline], CPU#1: syz.7.48/2535 WARNING: net/mptcp/pm_kernel.c:1074 at mptcp_pm_nl_set_flags+0x5de/0x640 net/mptcp/pm_kernel.c:1538, CPU#1: syz.7.48/2535 Modules linked in: CPU: 1 UID: 0 PID: 2535 Comm: syz.7.48 Not tainted 6.18.0-03987-gea5f5e676cf5 #17 PREEMPT(voluntary) Hardware name: QEMU Ubuntu 25.10 PC (i440FX + PIIX, 1996), BIOS 1.17.0-debian-1.17.0-1 04/01/2014 RIP: 0010:__mark_subflow_endp_available net/mptcp/pm_kernel.c:1074 [inline] RIP: 0010:mptcp_pm_nl_fullmesh net/mptcp/pm_kernel.c:1446 [inline] RIP: 0010:mptcp_pm_nl_set_flags_all net/mptcp/pm_kernel.c:1474 [inline] RIP: 0010:mptcp_pm_nl_set_flags+0x5de/0x640 net/mptcp/pm_kernel.c:1538 Code: 89 c7 e8 c5 8c 73 fe e9 f7 fd ff ff 49 83 ef 80 e8 b7 8c 73 fe 4c 89 ff be 03 00 00 00 e8 4a 29 e3 fe eb ac e8 a3 8c 73 fe 90 <0f> 0b 90 e9 3d ff ff ff e8 95 8c 73 fe b8 a1 ff ff ff eb 1a e8 89 RSP: 0018:ffffc9001535b820 EFLAGS: 00010287 netdevsim0: tun_chr_ioctl cmd 1074025677 RAX: ffffffff82da294d RBX: 0000000000000001 RCX: 0000000000080000 RDX: ffffc900096d0000 RSI: 00000000000006d6 RDI: 00000000000006d7 netdevsim0: linktype set to 823 RBP: ffff88802cdb2240 R08: 00000000000104ae R09: ffffffffffffffff R10: ffffffff82da27d4 R11: 0000000000000000 R12: 0000000000000000 R13: ffff88801246d8c0 R14: ffffc9001535b8b8 R15: ffff88802cdb1800 FS: 00007fc6ac5a76c0(0000) GS:ffff8880f90c8000(0000) knlGS:0000000000000000 netlink: 'syz.3.50': attribute type 5 has an invalid length. CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 netlink: 1232 bytes leftover after parsing attributes in process `syz.3.50'. CR2: 0000200000010000 CR3: 0000000025b1a000 CR4: 0000000000350ef0 Call Trace: mptcp_pm_set_flags net/mptcp/pm_netlink.c:277 [inline] mptcp_pm_nl_set_flags_doit+0x1d7/0x210 net/mptcp/pm_netlink.c:282 genl_family_rcv_msg_doit+0x117/0x180 net/netlink/genetlink.c:1115 genl_family_rcv_msg net/netlink/genetlink.c:1195 [inline] genl_rcv_msg+0x3a8/0x3f0 net/netlink/genetlink.c:1210 netlink_rcv_skb+0x16d/0x240 net/netlink/af_netlink.c:2550 genl_rcv+0x28/0x40 net/netlink/genetlink.c:1219 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x3e9/0x4c0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x4ab/0x5b0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg+0xc9/0xf0 net/socket.c:733 ____sys_sendmsg+0x272/0x3b0 net/socket.c:2608 ___sys_sendmsg+0x2de/0x320 net/socket.c:2662 __sys_sendmsg net/socket.c:2694 [inline] __do_sys_sendmsg net/socket.c:2699 [inline] __se_sys_sendmsg net/socket.c:2697 [inline] __x64_sys_sendmsg+0x110/0x1a0 net/socket.c:2697 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xed/0x360 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fc6adb66f6d Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 90 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 e8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fc6ac5a6ff8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e RAX: ffffffffffffffda RBX: 00007fc6addf5fa0 RCX: 00007fc6adb66f6d RDX: 0000000000048084 RSI: 00002000000002c0 RDI: 000000000000000e RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000000000000 ---truncated---

CVSS v3
5.5
EG Score
5.5(medium)
EG Risk
29(Track)
EG Risk 29/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity55% × 45%
Exploitation0% × 40%
Automatability30% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
1%
KEV
Not listed

Published

May 6, 2026

Last Modified

May 11, 2026

Advisory Details (6)

Auto-updated Aug 4, 2026
No patch confirmed yet.
generic

mptcp: pm: in-kernel: always set ID as avail when rm endp - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d90d73ad183566c81320d453a223f610a280f210
generic

mptcp: pm: in-kernel: always set ID as avail when rm endp - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/d191101dee25567c2af3b28565f45346c33d65f5
generic

mptcp: pm: in-kernel: always set ID as avail when rm endp - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7e4d88e36e5d0b8ffda637999cbca64c81701a81
generic

mptcp: pm: in-kernel: always set ID as avail when rm endp - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/7c1d221e475e3d8eb8ed4702392d43f8c5134d1f
generic

mptcp: pm: in-kernel: always set ID as avail when rm endp - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/4d480efd98e290c445f4ba476e4dcda5624b1aab
generic

mptcp: pm: in-kernel: always set ID as avail when rm endp - kernel/git/stable/linux.git - Linux kernel stable tree

https://git.kernel.org/stable/c/1b3ff4d88b508b73e2bbddb59356311efb7ba192

Patch Availability(15)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntulinux-tools-raspi-realtime-6.8 (6.8.0-2050.52) @ noble2026-08-23ubuntu
ubuntulinux-tools-realtime-hwe-22.04 (6.8.1-1056.57~22.04.2) @ jammy2026-08-23ubuntu
ubuntulinux-tools-gcp-fips-6.8 (6.8.0-1064.72+fips1) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-lts-24.04 (6.8.0-1058.61) @ noble2026-08-23ubuntu
ubuntulinux-tools-oracle-edge (6.8.0-1058.61~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-nvidia-lowlatency-64k-6.8 (6.8.0-1059.62.1) @ noble2026-08-23ubuntu
ubuntulinux-tools-aws-lts-24.04 (6.8.0-1061.64+1) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-lts-24.04 (6.8.0-1063.71) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fde-lts-24.04 (6.8.0-1062.69) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fips-6.8 (6.8.0-1063.71+fips2) @ noble2026-08-23ubuntu
ubuntulinux-tools-azure-fde-6.8 (6.8.0-1062.69~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-tools-aws-fips-6.8 (6.8.0-1061.64+fips1) @ noble2026-08-23ubuntu
ubuntulinux-tools-ibm-edge (6.8.0-1061.62~22.04.1) @ jammy2026-08-23ubuntu
ubuntulinux-virtual-hwe-22.04-edge (6.8.0-136.136~22.04.1) @ jammy2026-08-23ubuntu
linuxKernel @ 6.1.167—osv

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFixed inDependents
linux6.1.106-1 ... 6.1.99-1 (48 versions)6.1.170-1—
Debian:13(1)
PackageVulnerable rangeFixed inDependents
linux6.12.38-1 ... 6.12.85-1~bpo12+1 (17 versions)6.12.85-1—
Debian:14(1)
PackageVulnerable rangeFixed inDependents
linux6.12.100-1 ... 6.19~rc8-1~exp1 (116 versions)6.19.6-1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

All Vendor Advisories

(14)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 6× in last 7d / 30× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 171 total refreshes for this CVE.

  1. 2026-09-13 16:47 UTCEPSS rescore
  2. 2026-09-12 15:01 UTCEPSS rescore
  3. 2026-09-11 16:23 UTCOSV refresh
  4. 2026-09-11 14:53 UTCEPSS rescore
  5. 2026-09-10 09:34 UTCEPSS rescore
  6. 2026-09-08 22:00 UTCEPSS rescore
  7. 2026-09-07 16:01 UTCEPSS rescore
  8. 2026-09-06 13:47 UTCEPSS rescore
  9. 2026-09-04 05:06 UTCEPSS rescore
  10. 2026-09-02 14:12 UTCEPSS rescore
  11. 2026-09-01 13:54 UTCEPSS rescore
  12. 2026-08-30 19:17 UTCEPSS rescore
  13. 2026-08-30 01:22 UTCEPSS rescore
  14. 2026-08-28 21:41 UTCEPSS rescore
  15. 2026-08-27 14:25 UTCEPSS rescore
  16. 2026-08-26 14:46 UTCEPSS rescore
  17. 2026-08-25 13:49 UTCEPSS rescore
  18. 2026-08-23 19:54 UTCEG score recompute
  19. 2026-08-23 19:54 UTCVendor advisory
  20. 2026-08-23 19:54 UTCGHSA enrichment
  21. 2026-08-23 00:19 UTCEPSS rescore
  22. 2026-08-21 23:49 UTCEPSS rescore
  23. 2026-08-20 22:55 UTCEPSS rescore
  24. 2026-08-19 17:04 UTCEPSS rescore
  25. 2026-08-18 13:48 UTCEPSS rescore
Show 75 more
  1. 2026-08-17 13:47 UTCEPSS rescore
  2. 2026-08-17 12:54 UTCEG score recompute
  3. 2026-08-17 12:54 UTCVendor advisory
  4. 2026-08-17 12:54 UTCGHSA enrichment
  5. 2026-08-16 14:56 UTCEPSS rescore
  6. 2026-08-16 04:52 UTCEG score recompute
  7. 2026-08-16 04:52 UTCVendor advisory
  8. 2026-08-16 04:52 UTCGHSA enrichment
  9. 2026-08-15 01:30 UTCEPSS rescore
  10. 2026-08-14 03:26 UTCVendor advisory
  11. 2026-08-14 03:26 UTCGHSA enrichment
  12. 2026-08-12 23:42 UTCVendor advisory
  13. 2026-08-12 23:42 UTCGHSA enrichment
  14. 2026-08-12 00:36 UTCEG score recompute
  15. 2026-08-12 00:36 UTCVendor advisory
  16. 2026-08-12 00:36 UTCGHSA enrichment
  17. 2026-08-11 13:43 UTCEPSS rescore
  18. 2026-08-11 01:31 UTCEG score recompute
  19. 2026-08-11 01:31 UTCVendor advisory
  20. 2026-08-11 01:31 UTCGHSA enrichment
  21. 2026-08-11 00:00 UTCEPSS rescore
  22. 2026-08-10 01:40 UTCVendor advisory
  23. 2026-08-10 01:40 UTCGHSA enrichment
  24. 2026-08-09 02:34 UTCEG score recompute
  25. 2026-08-09 02:34 UTCVendor advisory
  26. 2026-08-09 02:34 UTCGHSA enrichment
  27. 2026-08-08 16:37 UTCEPSS rescore
  28. 2026-08-07 20:32 UTCVendor advisory
  29. 2026-08-07 20:32 UTCGHSA enrichment
  30. 2026-08-06 21:27 UTCEG score recompute
  31. 2026-08-06 21:27 UTCVendor advisory
  32. 2026-08-06 21:26 UTCGHSA enrichment
  33. 2026-08-06 13:46 UTCEPSS rescore
  34. 2026-08-05 22:20 UTCEG score recompute
  35. 2026-08-05 22:20 UTCVendor advisory
  36. 2026-08-05 22:20 UTCGHSA enrichment
  37. 2026-08-05 19:17 UTCEPSS rescore
  38. 2026-08-04 15:10 UTCEPSS rescore
  39. 2026-08-04 10:38 UTCEPSS rescore
  40. 2026-08-04 03:38 UTCEG score recompute
  41. 2026-08-04 03:38 UTCVendor advisory
  42. 2026-08-04 03:38 UTCGHSA enrichment
  43. 2026-08-03 10:36 UTCEPSS rescore
  44. 2026-08-03 04:29 UTCVendor advisory
  45. 2026-08-03 04:29 UTCGHSA enrichment
  46. 2026-08-02 05:07 UTCEG score recompute
  47. 2026-08-02 05:07 UTCVendor advisory
  48. 2026-08-02 05:07 UTCGHSA enrichment
  49. 2026-08-02 02:27 UTCEPSS rescore
  50. 2026-08-01 04:16 UTCEPSS rescore
  51. 2026-07-30 16:28 UTCEPSS rescore
  52. 2026-07-30 01:30 UTCEPSS rescore
  53. 2026-07-28 15:36 UTCEPSS rescore
  54. 2026-07-27 14:13 UTCEPSS rescore
  55. 2026-07-26 14:54 UTCEPSS rescore
  56. 2026-07-26 14:54 UTCEPSS rescore
  57. 2026-07-24 14:17 UTCEPSS rescore
  58. 2026-07-23 03:14 UTCEG score recompute
  59. 2026-07-22 14:08 UTCEPSS rescore
  60. 2026-07-21 15:24 UTCEPSS rescore
  61. 2026-07-20 23:02 UTCOSV refresh
  62. 2026-07-20 17:08 UTCEPSS rescore
  63. 2026-07-19 14:31 UTCEPSS rescore
  64. 2026-07-19 02:29 UTCEPSS rescore
  65. 2026-07-16 17:03 UTCEPSS rescore
  66. 2026-07-15 16:57 UTCEPSS rescore
  67. 2026-07-13 22:30 UTCEPSS rescore
  68. 2026-07-13 06:13 UTCEPSS rescore
  69. 2026-07-11 08:27 UTCEPSS rescore
  70. 2026-07-09 19:10 UTCEPSS rescore
  71. 2026-07-08 15:16 UTCEPSS rescore
  72. 2026-07-07 13:46 UTCEPSS rescore
  73. 2026-07-06 16:27 UTCEPSS rescore
  74. 2026-07-06 02:23 UTCEPSS rescore
  75. 2026-07-04 06:31 UTCEPSS rescore

Frequently asked(5)

What is CVE-2026-43252?
CVE-2026-43252 is a medium vulnerability published on May 6, 2026. In the Linux kernel, the following vulnerability has been resolved: mptcp: pm: in-kernel: always set ID as avail when rm endp Syzkaller managed to find a combination of actions that was generating this warning: WARNING: net/mptcp/pmkernel.c:1074 at marksubflowendpavailable…
When was CVE-2026-43252 disclosed?
CVE-2026-43252 was first published in the National Vulnerability Database on May 6, 2026, with the most recent update on May 11, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-43252 actively exploited?
CVE-2026-43252 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 99.3% of all scored CVEs.
What is the CVSS score of CVE-2026-43252?
CVE-2026-43252 has a CVSS v3 base score of 5.5 (NVD).
How do I remediate CVE-2026-43252?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-43252, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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