CVE-2026-98490

CRITICAL
INFO Priority: 0.06 BB Relevance: 80/100
Published: 2026-10-18 Modified: 2026-10-30 First seen: 2026-10-29 Status: active

Attack Surface

Network Low Complexity No Auth No Interaction Conf. Impact Integ. Impact

CVSS Vector Breakdown

AV: Network
AC: Low
PR: None
UI: None
S: Unchanged
C: High
I: High
A: High

Description

In the Linux kernel, the following vulnerability has been resolved: net: openvswitch: conntrack: fix helper UAF due to extensions realloc While calling the helpers, a raw pointer to the extensions area is wired into expectations list: -> nf_ct_helper() -> helper->help() -> nf_ct_expect_related_report() -> nf_ct_expect_insert() -> hlist_add_head_rcu(&exp->lnode, &master_help->expectations) In case the connection is not confirmed yet, more extensions can be added afterwards with *_ext_add() calls reallocating the extension space and leaving the now invalid pointer in the expectations list that is later accessed while removing the expectation. Make sure that helpers are called at the end after all the other extensions are already added. Note that the helper rejection now leaves the mark and labels set, but that's not different from how the NAT was handled before or how the mark and the labels were handled on confirmation failure. And there are no atomicity guarantees provided by the API anyway.

Affected Software (9)

VendorProductVersion
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < f53d13a286fb275bda0efdf445b8a1e4dfcb717b
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < 84d47a83b7b717576de0defab46b8823a22853b0
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < 9f308197395c1a524b736e401cbc8a2ed7d246c9
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < 18866dc1f525f9ee4de7709529d1ae1af8d8e8be
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < afcf362625190c5260530b1d6c7daa98831f6b83
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < 5f23080a625dd7855ab91485c8d691a54a1979f0
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < e02a83bb0b7a203f6a22f55ad5f426765560f811
Linux Linux cae3a2627520c3795b54533c5328b77af3405dbe < 1a4151e6be57b098b7a5ebfbde58585e83200cdc
Linux Linux 4.3

Bug Bounty Relevance

80 / 100
✓ Network accessible
✓ No authentication
✓ Low complexity
✓ No user interaction

CVSS Score

9.8 / 10.0 v3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS — Exploitation Probability

0.62%
Raw Score 0.006180
Percentile 49.6%
Date 2026-10-30

EPSS Trend

2026-10-30
0.00618
2026-10-29
0.00618
2026-10-28
0.00618

Intelligence Sources

mitre ref →
nvd ref →