PT-2025-4352 · Linux+7 · Linux Kernel+7

Kairui Song · Published 2025-01-07 · Updated 2025-11-12 · CVE-2025-21671

Positive Technologies (AI Summary)

CVSS v3.1

7.8

High

Base vector

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

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

Description The issue is related to a potential use-after-free (UAF) in the zram table. If zram meta alloc fails early, it frees the allocated zram->table without setting it to NULL, which can cause zram meta free to access the table if a user resets a failed and uninitialized device. This could potentially impact the confidentiality, integrity, and availability of protected information.

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

Exploit

Use After Free

Weakness Enumeration

CWE-416

Related Identifiers

ALSA-2025:20095

ALSA-2025:20518

ALT-PU-2025-3467

ALT-PU-2025-3500

BDU:2025-01394

CVE-2025-21671

DLA-4076-1

DSA-5860-1

INFSA-2025_20518

OPENSUSE-SU-2025_1177-1

OPENSUSE-SU-2025_1178-1

OPENSUSE-SU-2025_1180-1

RHSA-2025:20095

RHSA-2025:20518

RHSA-2025_20518

SUSE-SU-2025:01919-1

SUSE-SU-2025:1177-1

SUSE-SU-2025:1178-1

SUSE-SU-2025:1180-1

SUSE-SU-2025:20190-1

SUSE-SU-2025:20192-1

SUSE-SU-2025:20260-1

SUSE-SU-2025:20270-1

SUSE-SU-2025_1177-1

SUSE-SU-2025_1178-1

SUSE-SU-2025_1180-1

Affected Products

Alt Linux

Almalinux

Astra Linux

Linux Kernel

Red Hat

Red Os

Rocky Linux

Suse

References · 1573

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/21xxx/CVE-2025-21671.json · Exploit
• https://osv.dev/vulnerability/DSA-5860-1 · Vendor Advisory
• https://wiki.astralinux.ru/astra-linux-se17-bulletin-2025-0923SE17 · Vendor Advisory
• https://osv.dev/vulnerability/SUSE-SU-2025:01919-1 · Vendor Advisory
• https://errata.almalinux.org/9/ALSA-2025-20518.html · Vendor Advisory
• https://git.kernel.org/stable/c/fe3de867f94819ba0f28e035c0b0182150147d95 · Patch
• https://osv.dev/vulnerability/SUSE-SU-2025:1180-1 · Vendor Advisory
• https://linux.oracle.com/errata/ELSA-2025-20518-0.html · Vendor Advisory
• https://git.kernel.org/stable/c/902ef8f16d5ca77edc77c30656be54186c1e99b7 · Patch
• https://osv.dev/vulnerability/SUSE-SU-2025:1177-1 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2025-21671 · Security Note
• https://errata.rockylinux.org/RLSA-2025:20518 · Vendor Advisory
• https://cve.org/CVERecord?id=CVE-2025-21671 · Security Note
• https://git.kernel.org/stable/c/571d3f6045cd3a6d9f6aec33b678f3ffe97582ef · Patch
• https://git.kernel.org/stable/c/212fe1c0df4a150fb6298db2cfff267ceaba5402 · Patch