PT-2025-8878 · Linux+6 · Linux Kernel+6

Eric Dumazet · Published 2025-02-07 · Updated 2026-04-20 · CVE-2025-21766

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A vulnerability in the Linux kernel has been resolved. The issue concerns the ip rt update pmtu() function, which must use RCU protection to prevent the net structure it reads from disappearing.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

Weakness Enumeration

CWE-413

Related Identifiers

BDU:2025-12056

CVE-2025-21766

DLA-4102-1

OESA-2025-1446

OESA-2025-1450

OPENSUSE-SU-2025_1177-1

OPENSUSE-SU-2025_1178-1

OPENSUSE-SU-2025_1180-1

SUSE-SU-2025:01919-1

SUSE-SU-2025:01951-1

SUSE-SU-2025:01967-1

SUSE-SU-2025:1177-1

SUSE-SU-2025:1178-1

SUSE-SU-2025:1180-1

SUSE-SU-2025:1293-1

SUSE-SU-2025:20190-1

SUSE-SU-2025:20192-1

SUSE-SU-2025:20260-1

SUSE-SU-2025:20270-1

SUSE-SU-2025_01951-1

SUSE-SU-2025_01967-1

SUSE-SU-2025_1177-1

SUSE-SU-2025_1178-1

SUSE-SU-2025_1180-1

SUSE-SU-2025_1293-1

SUSE-SU-2026:0474-1

SUSE-SU-2026:0475-1

SUSE-SU-2026:0495-1

SUSE-SU-2026:0496-1

SUSE-SU-2026:0617-1

SUSE-SU-2026:1131-1

USN-7510-1

USN-7510-2

USN-7510-3

USN-7510-4

USN-7510-5

USN-7510-6

USN-7510-7

USN-7510-8

USN-7511-1

USN-7511-2

USN-7511-3

USN-7512-1

USN-7521-1

USN-7521-2

USN-7521-3

USN-7593-1

USN-7602-1

USN-7703-1

USN-7703-2

USN-7703-3

USN-7703-4

USN-7719-1

USN-7737-1

Affected Products

Astra Linux

Debian

Linuxmint

Linux Kernel

Red Os

Suse

Ubuntu

References · 3056

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21766.json · Exploit
• https://ubuntu.com/security/CVE-2024-57997 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-21780 · Security Note
• https://ubuntu.com/security/CVE-2025-21871 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-21941 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2025-21927 · Security Note
• https://nvd.nist.gov/vuln/detail/CVE-2025-21914 · Security Note
• https://osv.dev/vulnerability/USN-7593-1 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-21864 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-21791 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-46821 · Vendor Advisory
• https://ubuntu.com/security/CVE-2025-21820 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-8805 · Vendor Advisory
• https://ubuntu.com/security/CVE-2024-58082 · Vendor Advisory
• https://ubuntu.com/security/notices/USN-7510-6 · Vendor Advisory