CVE-2025-21671: zram: fix potential UAF of zram table

Modified

AliasesUBUNTU-CVE-2025-21671DEBIAN-CVE-2025-21671

Published 31-01-2025Last modified 11-05-2026

Vulnerability summary

CVE-2025-21671 is a high (CVSS 7.8) Use After Free vulnerability in linux. EPSS estimates a 0.22% chance of exploitation in the next 30 days, higher than 12% of scored vulnerabilities.

Priority

Routine

Not severe (CVSS 7.8, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?

CVSS score

7.8/10

010

High · v3.1 (CVE.org)

EPSS score

0.22%

0%100%

Low · 0.00 pp in 30 days

KEVNot listedNot listed by any tracked catalog.

RansomwareNot flaggedNo ransomware use recorded.

Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 12 · Related 8

DLA-4076-1 DSA-5860-1 RHSA-2025:20095 RHSA-2025:20518 SUSE-SU-2025:01919-1 SUSE-SU-2025:1177-1+6 more

Timeline

31-01-2025
PublishedVulnerability first disclosed.
11-05-2026
Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: zram: fix potential UAF of zram table If zram_meta_alloc failed early, it frees allocated zram->table without setting it NULL. Which will potentially cause zram_meta_free to access the table if user reset an failed and uninitialized device.

CVSS metrics

4 scores · 4 sources · 1 version

v3.17.8

EPSS trend

Probability

0.22%

Chance of exploitation in the next 30 days

Percentile

12%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.22% on 04-10-2026

04-10-202603-11-2026

Known exploited

Compare KEV catalogs

CISA KEV

Not in the CISA KEV catalog.

ENISA CNW

Not in the ENISA CNW catalog.

CIRCL

Not in the CIRCL catalog.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

CWE-416Use After FreeThe product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory "belongs" to the code that operates on the new pointer.

Affected systems

Version check

Known conditions: local access, low-privilege account, no user interaction (CVSS vector). Other conditions: not stated in public data.

Ubuntu77 products

linux-allwinner-5.19All versions (No fix recorded)
linux-aws-5.0All versions (No fix recorded)
linux-aws-5.11All versions (No fix recorded)
linux-aws-5.13All versions (No fix recorded)
linux-aws-5.19All versions (No fix recorded)

linux-aws-5.3All versions (No fix recorded)
linux-aws-5.8All versions (No fix recorded)
linux-aws-6.2All versions (No fix recorded)
linux-aws-6.5All versions (No fix recorded)
linux-azureAll versions (No fix recorded)
linux-azure-5.11All versions (No fix recorded)
linux-azure-5.13All versions (No fix recorded)
linux-azure-5.19All versions (No fix recorded)
linux-azure-5.3All versions (No fix recorded)
linux-azure-5.8All versions (No fix recorded)
linux-azure-6.2All versions (No fix recorded)
linux-azure-6.5All versions (No fix recorded)
linux-azure-edgeAll versions (No fix recorded)
linux-azure-fdeAll versions (No fix recorded)
linux-azure-fde-5.19All versions (No fix recorded)
linux-azure-fde-6.2All versions (No fix recorded)
linux-gcpAll versions (No fix recorded)
linux-gcp-5.11All versions (No fix recorded)
linux-gcp-5.13All versions (No fix recorded)
linux-gcp-5.19All versions (No fix recorded)
linux-gcp-5.3All versions (No fix recorded)
linux-gcp-5.8All versions (No fix recorded)
linux-gcp-6.2All versions (No fix recorded)
linux-gcp-6.5All versions (No fix recorded)
linux-gkeAll versions (No fix recorded)
linux-gke-4.15All versions (No fix recorded)
linux-gke-5.15All versions (No fix recorded)
linux-gke-5.4All versions (No fix recorded)
linux-gkeopAll versions (No fix recorded)
linux-gkeop-5.15All versions (No fix recorded)
linux-gkeop-5.4All versions (No fix recorded)
linux-hweAll versions (No fix recorded)
linux-hwe-5.11All versions (No fix recorded)
linux-hwe-5.13All versions (No fix recorded)
linux-hwe-5.19All versions (No fix recorded)
linux-hwe-5.8All versions (No fix recorded)
linux-hwe-6.2All versions (No fix recorded)
linux-hwe-6.5All versions (No fix recorded)
linux-hwe-edgeAll versions (No fix recorded)
linux-intel-5.13All versions (No fix recorded)
linux-intel-iot-realtimeAll versions (No fix recorded)
linux-lowlatency-hwe-5.19All versions (No fix recorded)
linux-lowlatency-hwe-6.2All versions (No fix recorded)
linux-lowlatency-hwe-6.5All versions (No fix recorded)
linux-nvidia-6.2All versions (No fix recorded)
linux-nvidia-6.5All versions (No fix recorded)
linux-oemAll versions (No fix recorded)
linux-oem-5.10All versions (No fix recorded)
linux-oem-5.13All versions (No fix recorded)
linux-oem-5.14All versions (No fix recorded)
linux-oem-5.17All versions (No fix recorded)
linux-oem-5.6All versions (No fix recorded)
linux-oem-6.0All versions (No fix recorded)
linux-oem-6.1All versions (No fix recorded)
linux-oem-6.5All versions (No fix recorded)
linux-oracle-5.0All versions (No fix recorded)
linux-oracle-5.11All versions (No fix recorded)
linux-oracle-5.13All versions (No fix recorded)
linux-oracle-5.3All versions (No fix recorded)
linux-oracle-5.8All versions (No fix recorded)
linux-oracle-6.5All versions (No fix recorded)
linux-raspi-realtimeAll versions (No fix recorded)
linux-raspi2All versions (No fix recorded)
linux-realtimeAll versions (No fix recorded)
linux-riscvAll versions (No fix recorded)
linux-riscv-5.11All versions (No fix recorded)
linux-riscv-5.19All versions (No fix recorded)
linux-riscv-5.8All versions (No fix recorded)
linux-riscv-6.5All versions (No fix recorded)
linux-starfive-5.19All versions (No fix recorded)
linux-starfive-6.2All versions (No fix recorded)
linux-starfive-6.5All versions (No fix recorded)

Show all 77

Linux2 products

linux≥ ac3b5366b9b7c9d97b606532ceab43d2329a22f3, < fe3de867f94819ba0f28e035c0b0182150147d95 | ≥ 0b5b0b65561b34e6e360de317e4bcd031bfabf42, < 571d3f6045cd3a6d9f6aec33b678f3ffe97582ef | ≥ 6fb92e9a52e3feae309a213950f21dfcd1eb0b40, < 902ef8f16d5ca77edc77c30656be54186c1e99b7 | ≥ 74363ec674cb172d8856de25776c8f3103f05e2f, < 212fe1c0df4a150fb6298db2cfff267ceaba5402 | ≥ 6.1.122, < 6.1.127 | ≥ 6.6.68, < 6.6.74 | ≥ 6.12.7, < 6.12.11
linux_kernel≥ 6.1.122, < 6.1.127 | ≥ 6.6.68, < 6.6.74 | ≥ 6.12.7, < 6.12.11

Debian1 product

linux< 6.1.128-1 | < 6.12.11-1

3 vendors · 80 products

References

9 links