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CVE-2026-74577

Updated on 15 Aug 2026

Severity

3.3 Low severity

Details

CVSS score: 3.3
Affected product
Affected component
Links: NIST CIRCL RHEL Ubuntu

Overview

About vulnerability

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

net: mpls: initialize rtm_tos in mpls_getroute()

mpls_getroute() builds the RTM_NEWROUTE reply to an RTM_GETROUTE request by filling a struct rtmsg allocated from an skb whose data area is not zeroed (alloc_skb(NLMSG_GOODSIZE, …)). It sets every field of the header except rtm_tos:

r = nlmsg_data(nlh); r->rtm_family = AF_MPLS; r->rtm_dst_len = 20; r->rtm_src_len = 0; r->rtm_table = RT_TABLE_MAIN; r->rtm_type = RTN_UNICAST; r->rtm_scope = RT_SCOPE_UNIVERSE; r->rtm_protocol = rt->rt_protocol; r->rtm_flags = 0;

struct rtmsg has no padding, so the one uninitialised byte rtm_tos (offset 3) is copied straight to user space on recvmsg(), leaking a byte of uninitialised heap memory. This is in contrast to mpls_dump_route(), which fills the very same header and does set rtm_tos = 0.

Initialize rtm_tos to 0, matching mpls_dump_route().

Reproduced with KMSAN by adding an MPLS route and issuing a non-RTM_F_FIB_MATCH RTM_GETROUTE for its label:

BUG: KMSAN: kernel-infoleak in _copy_to_iter+0x36c/0x33f0 _copy_to_iter+0x36c/0x33f0 __skb_datagram_iter+0x196/0x12c0 skb_copy_datagram_iter+0x5b/0x210 netlink_recvmsg+0x37b/0xef0 … Uninit was created at: __alloc_skb+0x8ca/0x10e0 mpls_getroute+0x1280/0x3a40 rtnetlink_rcv_msg+0x1138/0x15a0 … Byte 19 of 64 is uninitialized

(byte 19 = nlmsghdr(16) + rtmsg offset 3 = rtm_tos)

Details

Affected product:: AlmaLinux 9.2 ESU , Amazon Linux 2 ELS , CentOS 8.4 ELS , CentOS 8.5 ELS , CentOS Stream 8 ELS , Debian 10 ELS , Debian 11 ELS , Oracle Linux 7 ELS , TuxCare 9.6 ESU , TuxCare 9.8 ESU , Ubuntu 16.04 ELS , Ubuntu 18.04 ELS , Ubuntu 20.04 ELS
Affected packages:: linux @ 5.10.269 (+12 more)

Fixes

Operating system / Project

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system	Status	Covered kernels
Debian 12	Released	43 kernels 6.1.38-1 6.1.38-2 6.1.38-4 6.1.52-1 6.1.55-1 6.1.64-1 6.1.66-1 6.1.69-1 6.1.76-1 6.1.27-1 6.1.67-1 6.1.85-1 6.1.90-1 6.1.94-1 6.1.99-1 6.1.106-3 6.1.112-1 6.1.115-1 6.1.119-1 6.1.123-1 6.1.128-1 6.1.124-1 6.1.129-1 6.1.133-1 6.1.135-1 6.1.137-1 6.1.140-1 6.1.139-1 6.1.147-1 6.1.148-1 6.1.153-1 6.1.158-1 6.1.159-1 6.1.162-1 6.1.164-1 6.1.170-1 6.1.170-3 6.1.172-1 6.1.174-1 6.1.170-2 6.1.176-1 6.1.177-1 6.1.180-1
Debian 13	Released	15 kernels 6.12.85-1 6.12.86-1 6.12.88-1 6.12.74-2 6.12.73-1 6.12.63-1 6.12.69-1 6.12.74-1 6.12.90-1 6.12.90-2 6.12.94-1 6.12.95-1 6.12.96-1 6.12.100-1 6.12.101-1
Oracle Linux 8 UEK 7	Released	112 kernels 5.15.0-102.110.5.el8uek 5.15.0-101.103.2.1.el8uek 5.15.0-8.91.4.1.el8uek 5.15.0-7.86.6.1.el8uek 5.15.0-2.52.3.el8uek 5.15.0-100.96.32.el8uek 5.15.0-5.76.5.1.el8uek 5.15.0-6.80.3.1.el8uek 5.15.0-3.60.5.1.el8uek 5.15.0-0.30.20.el8uek 5.15.0-1.43.4.1.el8uek 5.15.0-0.30.20.1.el8uek 5.15.0-1.43.4.2.el8uek 5.15.0-4.70.5.2.el8uek 5.15.0-104.119.4.2.el8uek 5.15.0-0.30.19.el8uek 5.15.0-105.125.6.2.el8uek 5.15.0-105.125.6.2.1.el8uek 5.15.0-105.125.6.2.2.el8uek 5.15.0-106.131.4.el8uek 5.15.0-200.131.27.el8uek 5.15.0-200.131.27.1.el8uek 5.15.0-201.135.6.el8uek 5.15.0-202.135.2.el8uek 5.15.0-102.110.5.1.el8uek 5.15.0-103.114.4.el8uek 5.15.0-203.146.5.1.el8uek 5.15.0-204.147.6.2.el8uek 5.15.0-204.147.6.3.el8uek 5.15.0-205.149.5.1.el8uek 5.15.0-205.149.5.4.el8uek 5.15.0-206.153.7.el8uek 5.15.0-206.153.7.1.el8uek 5.15.0-207.156.6.el8uek 5.15.0-208.159.3.el8uek 5.15.0-208.159.3.2.el8uek 5.15.0-209.161.7.el8uek 5.15.0-209.161.7.1.el8uek 5.15.0-209.161.7.2.el8uek 5.15.0-210.163.7.el8uek 5.15.0-300.163.18.el8uek 5.15.0-300.163.18.1.el8uek 5.15.0-300.163.18.1.1.el8uek 5.15.0-301.163.5.2.el8uek 5.15.0-302.167.6.el8uek 5.15.0-300.163.18.7.el8uek 5.15.0-302.167.6.1.el8uek 5.15.0-303.171.5.2.el8uek 5.15.0-303.171.5.2.1.el8uek 5.15.0-304.171.4.el8uek 5.15.0-304.171.4.1.el8uek 5.15.0-304.171.4.3.el8uek 5.15.0-303.171.5.2.2.el8uek 5.15.0-305.176.4.el8uek 5.15.0-306.177.4.el8uek 5.15.0-306.177.4.1.el8uek 5.15.0-307.178.5.el8uek 5.15.0-308.179.6.el8uek 5.15.0-308.179.6.2.el8uek 5.15.0-308.179.6.3.el8uek 5.15.0-309.180.4.el8uek 5.15.0-308.179.6.7.el8uek 5.15.0-309.180.4.2.el8uek 5.15.0-308.179.6.11.el8uek 5.15.0-310.184.5.2.el8uek 5.15.0-310.184.5.3.el8uek 5.15.0-311.185.9.el8uek 5.15.0-308.179.6.14.el8uek 5.15.0-312.187.5.el8uek 5.15.0-312.187.5.1.el8uek 5.15.0-312.187.5.2.el8uek 5.15.0-312.187.5.3.el8uek 5.15.0-308.179.6.16.el8uek 5.15.0-313.189.5.1.el8uek 5.15.0-313.189.5.2.el8uek 5.15.0-313.189.5.3.el8uek 5.15.0-314.193.5.3.el8uek 5.15.0-314.193.5.4.el8uek 5.15.0-314.193.5.5.el8uek 5.15.0-315.196.5.1.el8uek 5.15.0-315.196.5.2.el8uek 5.15.0-316.196.4.1.el8uek 5.15.0-316.196.4.2.el8uek 5.15.0-317.197.5.1.el8uek 5.15.0-317.197.5.2.el8uek 5.15.0-318.199.3.2.el8uek 5.15.0-318.199.3.2.1.el8uek 5.15.0-319.201.4.2.el8uek 5.15.0-319.201.4.3.el8uek 5.15.0-319.201.4.4.el8uek 5.15.0-319.201.4.6.el8uek 5.15.0-320.202.8.2.el8uek 5.15.0-320.202.8.3.el8uek 5.15.0-320.202.8.4.el8uek 5.15.0-320.202.8.5.el8uek 5.15.0-318.199.3.6.el8uek 5.15.0-321.202.5.el8uek 5.15.0-321.202.5.1.el8uek 5.15.0-321.202.5.2.el8uek 5.15.0-321.202.5.3.el8uek 5.15.0-322.203.3.2.el8uek 5.15.0-322.203.3.3.el8uek 5.15.0-322.203.3.4.el8uek 5.15.0-322.203.3.4.5.el8uek 5.15.0-308.179.6.18.el8uek 5.15.0-318.199.3.7.el8uek 5.15.0-322.203.3.5.el8uek 5.15.0-322.203.3.4.1.el8uek 5.15.0-323.211.3.3.el8uek 5.15.0-323.211.3.4.el8uek 5.15.0-323.211.3.5.el8uek 5.15.0-308.179.6.19.el8uek
Oracle Linux 9 UEK 7	Released	112 kernels 5.15.0-101.103.2.1.el9uek 5.15.0-8.91.4.1.el9uek 5.15.0-7.86.6.1.el9uek 5.15.0-5.76.5.1.el9uek 5.15.0-6.80.3.1.el9uek 5.15.0-3.60.5.1.el9uek 5.15.0-0.30.20.el9uek 5.15.0-100.96.32.el9uek 5.15.0-1.43.4.2.el9uek 5.15.0-2.52.3.el9uek 5.15.0-4.70.5.2.el9uek 5.15.0-1.43.4.1.el9uek 5.15.0-0.30.20.1.el9uek 5.15.0-102.110.5.el9uek 5.15.0-102.110.5.1.el9uek 5.15.0-103.114.4.el9uek 5.15.0-104.119.4.2.el9uek 5.15.0-0.30.19.el9uek 5.15.0-105.125.6.2.el9uek 5.15.0-105.125.6.2.1.el9uek 5.15.0-105.125.6.2.2.el9uek 5.15.0-106.131.4.el9uek 5.15.0-200.131.27.el9uek 5.15.0-200.131.27.1.el9uek 5.15.0-201.135.6.el9uek 5.15.0-202.135.2.el9uek 5.15.0-203.146.5.1.el9uek 5.15.0-204.147.6.2.el9uek 5.15.0-204.147.6.3.el9uek 5.15.0-205.149.5.1.el9uek 5.15.0-205.149.5.4.el9uek 5.15.0-206.153.7.el9uek 5.15.0-206.153.7.1.el9uek 5.15.0-207.156.6.el9uek 5.15.0-208.159.3.el9uek 5.15.0-208.159.3.2.el9uek 5.15.0-209.161.7.el9uek 5.15.0-209.161.7.1.el9uek 5.15.0-209.161.7.2.el9uek 5.15.0-210.163.7.el9uek 5.15.0-300.163.18.el9uek 5.15.0-300.163.18.1.el9uek 5.15.0-300.163.18.1.1.el9uek 5.15.0-301.163.5.2.el9uek 5.15.0-302.167.6.el9uek 5.15.0-300.163.18.7.el9uek 5.15.0-302.167.6.1.el9uek 5.15.0-303.171.5.2.el9uek 5.15.0-303.171.5.2.1.el9uek 5.15.0-304.171.4.el9uek 5.15.0-304.171.4.1.el9uek 5.15.0-304.171.4.3.el9uek 5.15.0-303.171.5.2.2.el9uek 5.15.0-305.176.4.el9uek 5.15.0-306.177.4.el9uek 5.15.0-306.177.4.1.el9uek 5.15.0-307.178.5.el9uek 5.15.0-308.179.6.el9uek 5.15.0-308.179.6.2.el9uek 5.15.0-308.179.6.3.el9uek 5.15.0-309.180.4.el9uek 5.15.0-308.179.6.7.el9uek 5.15.0-309.180.4.2.el9uek 5.15.0-308.179.6.11.el9uek 5.15.0-310.184.5.2.el9uek 5.15.0-310.184.5.3.el9uek 5.15.0-311.185.9.el9uek 5.15.0-308.179.6.14.el9uek 5.15.0-312.187.5.el9uek 5.15.0-312.187.5.1.el9uek 5.15.0-312.187.5.2.el9uek 5.15.0-312.187.5.3.el9uek 5.15.0-308.179.6.16.el9uek 5.15.0-313.189.5.1.el9uek 5.15.0-313.189.5.2.el9uek 5.15.0-313.189.5.3.el9uek 5.15.0-314.193.5.3.el9uek 5.15.0-314.193.5.4.el9uek 5.15.0-314.193.5.5.el9uek 5.15.0-315.196.5.1.el9uek 5.15.0-315.196.5.2.el9uek 5.15.0-316.196.4.1.el9uek 5.15.0-316.196.4.2.el9uek 5.15.0-317.197.5.1.el9uek 5.15.0-317.197.5.2.el9uek 5.15.0-318.199.3.2.el9uek 5.15.0-318.199.3.2.1.el9uek 5.15.0-319.201.4.2.el9uek 5.15.0-319.201.4.3.el9uek 5.15.0-319.201.4.4.el9uek 5.15.0-319.201.4.6.el9uek 5.15.0-320.202.8.2.el9uek 5.15.0-320.202.8.3.el9uek 5.15.0-320.202.8.4.el9uek 5.15.0-320.202.8.5.el9uek 5.15.0-318.199.3.6.el9uek 5.15.0-321.202.5.el9uek 5.15.0-321.202.5.1.el9uek 5.15.0-321.202.5.2.el9uek 5.15.0-321.202.5.3.el9uek 5.15.0-322.203.3.2.el9uek 5.15.0-322.203.3.3.el9uek 5.15.0-322.203.3.4.el9uek 5.15.0-322.203.3.4.5.el9uek 5.15.0-308.179.6.18.el9uek 5.15.0-318.199.3.7.el9uek 5.15.0-322.203.3.5.el9uek 5.15.0-322.203.3.4.1.el9uek 5.15.0-323.211.3.3.el9uek 5.15.0-323.211.3.4.el9uek 5.15.0-323.211.3.5.el9uek 5.15.0-308.179.6.19.el9uek
Ubuntu 22.04	Planned	—
Ubuntu 22.04 AWS	Planned	—
Ubuntu 22.04 Azure	Planned	—

Release info

Copy page link

Open as a page

Advisory

CLSA-2025:1748945064

Operating system

CentOS 8.4 ELS

Published date

Nov 16, 2014

Project

Linux

Version

2.11.0-1~ubuntu16.04.1+tuxcare.els12

How to fix

Update command:

apt-get update
apt-get --only-upgrade install ansible*

Changelog

Insufficiently Random Passwords Leakage
Debian/patches/CVE-2020-10729.patch: Fix caching of Jinja2 expressions to prevent caching dynamic results
CVE-2020-10729

Updated packages

ansible_2.5.1+dfsg-1ubuntu0.1+tuxcare.els6_all.deb

CVE-2026-74577

Severity

Details

Overview

About vulnerability

Details

Statement

Fixes

Statement

KernelCare state

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