Is there a patch available for CVE-2026-99139?

Yes, a patch is available for CVE-2026-99139. Update the affected software to the latest version immediately.

Linux CVE-2026-99139

EUVD-2026-111891

2026-10-28 Linux

GHSA-48cq-p2fm-8444

Information Disclosure Linux

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Awaiting Data No severity or threat signals available yet. Label will update when CVSS score is published or threat intelligence arrives.

Patch available

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AnalysisCVE.org

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

tcp: fix use-after-free in do_tcp_getsockopt(TCP_CONGESTION)

do_tcp_getsockopt() reads icsk->icsk_ca_ops->name without holding rcu_read_lock(). Since commit 0baf26b0fcd7 ("bpf: tcp: Support tcp_congestion_ops in bpf"), icsk_ca_ops can point to dynamically allocated BPF struct_ops memory that may be freed concurrently via setsockopt(TCP_CONGESTION), leading to a use-after-free.

BUG: KASAN: slab-use-after-free in _copy_to_user+0x37/0x60 Read of size 16 at addr ffff888013505260 by task exploit/149 _copy_to_user+0x37/0x60 do_tcp_getsockopt+0x158a/0x2460 (net/ipv4/tcp.c:4585) tcp_getsockopt+0x91/0xf0 __sys_getsockopt+0xf7/0x170

Fix this by holding rcu_read_lock() around the ca_ops->name access, using READ_ONCE() to load icsk_ca_ops, and copying the name to a stack buffer before releasing the lock. Also annotate the relevant icsk_ca_ops stores with WRITE_ONCE() to fix the accompanying KCSAN data-race issue.

Affected VersionsENISA

Linux 0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 <a8e45471afa230c1431c26c8e99ec24377e3b514

Linux patch: 6.18.59

Linux 0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 <c1804ef016392dd91267d2207ee43b1de34302ca

Linux patch: 7.3

Linux patch: 0

Linux patch: 7.2.13

Linux 0baf26b0fcd74bbfcef53c5d5e8bad2b99c8d0d2 <5271b79b7ad68dcb222e893773f92bdabf7750f3

Linux 5.6

Affected Packages

euvd linux no fix

Source: OSV (Open Source Vulnerabilities)

Affects your stack

Affects 1 package in euvd

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Exploit and PoC references, threat intelligence from 22 sources

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Lifecycle Timeline

Patch available

Oct 28, 2026 - 11:02 EUVD

CVE Published

Oct 28, 2026 - 10:34 cve.org

UNKNOWN (no severity yet)

Threat Intelligence Overview

Data Quality

2 sources

Confidence: Low

EUVD

CVE.org

How this decision was reached

The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.

SignalValue

Severity Not scored yet

CISA KEV No

Public POC No

EPSS N/A

Patch available Yes

Active threat No

What every action level means

Emergency Immediate action required. Criteria: CRITICAL + in CISA KEV (actively exploited) without patch, OR CRITICAL + EPSS > 30% without patch, OR CRITICAL + active threat signals without patch.

Act Now Prioritize within 24-48h. Criteria: in KEV with patch available, OR CRITICAL + public POC, OR HIGH + EPSS > 10%, OR CRITICAL + active threat, OR any CRITICAL severity.

This Week Schedule remediation this week. Criteria: HIGH severity (CVSS 7.0-8.9). Patch within normal change window.

This Month Plan within 30 days. Criteria: MEDIUM severity (CVSS 4.0-6.9), lower exploitation probability. Include in regular patch cycle.

Monitor Track and reassess. Criteria: LOW severity (CVSS 0.1-3.9), minimal exploitation risk. No immediate action needed.

Awaiting Data No severity or threat signals available yet. Label will update when CVSS score is published or threat intelligence arrives.

Attack Technique

Information Disclosure MEDIUM

Information disclosure occurs when an application unintentionally exposes sensitive data that aids attackers in reconnaissance or directly compromises security.