7.8

CVE-2026-46259: procfs: fix missing RCU protection when reading real_parent in do_task_stat()

Modified
AliasesUBUNTU-CVE-2026-46259DEBIAN-CVE-2026-46259
Published 03-06-2026Last modified 19-10-2026

Vulnerability summary

CVE-2026-46259 is a high (CVSS 7.8) Use After Free vulnerability in linux. EPSS estimates a 0.12% chance of exploitation in the next 30 days, higher than 1.9% 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
0.12%
0%100%
Low · -0.06 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 43 · Related 37
LSN-0121-1LSN-0122-1OPENSUSE-SU-2026:21388-1RHSA-2026:36018RHSA-2026:36348RHSA-2026:36349

Timeline

  1. 03-06-2026
    PublishedVulnerability first disclosed.
  2. 19-10-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: procfs: fix missing RCU protection when reading real_parent in do_task_stat() When reading /proc/[pid]/stat, do_task_stat() accesses task->real_parent without proper RCU protection, which leads to: cpu 0 cpu 1 ----- ----- do_task_stat var = task->real_parent release_task call_rcu(delayed_put_task_struct) task_tgid_nr_ns(var) rcu_read_lock <--- Too late to protect task->real_parent! task_pid_ptr <--- UAF! rcu_read_unlock This patch uses task_ppid_nr_ns() instead of task_tgid_nr_ns() to add proper RCU protection for accessing task->real_parent.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.12%

Chance of exploitation in the next 30 days

Percentile

2%

Versus all other CVEs

30-day change

Decrease -0.06 pp

From 0.18% 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

Affected systems

Version check

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

Ubuntu157 products
  • linuxAll versions (No fix recorded) | < 5.15.0-186.196 | < 6.8.0-134.134
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-awsAll versions (No fix recorded) | < 5.15.0-1112.119 | < 6.8.0-1060.63
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Linux2 products
  • linux≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < fefa0fcd78be465b7ad4c497fa6ec90d64194c04 | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < c93a33f28f915d446eea6fb3f0e1def0b3af1982 | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < 1c8dc5b5517546c68ffae40b948336122bb61306 | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < 0e64bd46a04a4fd61279aca9f53a664e9e5f7e7e | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < 73ec7c96601d61d52310c659145bb06d933a0fa6 | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < 4f9ae386861e280b7631ca252f798d25575627ee | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < dd8b13cb4ff1a4545a214ed897fdf2bc341155b6 | ≥ 06fffb1267c9d986687b69d74a46ee332a50575e, < 76149d53502cf17ef3ae454ff384551236fba867 | 2.6.26
  • linux_kernel≥ 2.6.26, < 5.10.252 | ≥ 5.11, < 5.15.202 | ≥ 5.16, < 6.1.165 | ≥ 6.2, < 6.6.128 | ≥ 6.7, < 6.12.75 | ≥ 6.13, < 6.18.14 | ≥ 6.19, < 6.19.4
Debian1 product
  • linux< 6.1.170-1 | < 6.12.85-1 | < 6.18.14-1

3 vendors · 160 products

References

37 links
Show all 37 references