7.8

CVE-2025-39780: sched/ext: Fix invalid task state transitions on class switch

Modified
AliasesUBUNTU-CVE-2025-39780DEBIAN-CVE-2025-39780
Published 11-09-2025Last modified 05-08-2026

Vulnerability summary

CVE-2025-39780 is a high (CVSS 7.8) vulnerability in linux. EPSS estimates a 0.15% chance of exploitation in the next 30 days, higher than 4.5% 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
0.15%
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 1
DSA-6008-1

Timeline

  1. 11-09-2025
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: sched/ext: Fix invalid task state transitions on class switch When enabling a sched_ext scheduler, we may trigger invalid task state transitions, resulting in warnings like the following (which can be easily reproduced by running the hotplug selftest in a loop): sched_ext: Invalid task state transition 0 -> 3 for fish[770] WARNING: CPU: 18 PID: 787 at kernel/sched/ext.c:3862 scx_set_task_state+0x7c/0xc0 ... RIP: 0010:scx_set_task_state+0x7c/0xc0 ... Call Trace: <TASK> scx_enable_task+0x11f/0x2e0 switching_to_scx+0x24/0x110 scx_enable.isra.0+0xd14/0x13d0 bpf_struct_ops_link_create+0x136/0x1a0 __sys_bpf+0x1edd/0x2c30 __x64_sys_bpf+0x21/0x30 do_syscall_64+0xbb/0x370 entry_SYSCALL_64_after_hwframe+0x77/0x7f This happens because we skip initialization for tasks that are already dead (with their usage counter set to zero), but we don't exclude them during the scheduling class transition phase. Fix this by also skipping dead tasks during class swiching, preventing invalid task state transitions.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.15%

Chance of exploitation in the next 30 days

Percentile

5%

Versus all other CVEs

30-day change

No change 0.00 pp

From 0.15% 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

No weakness data has been published for this record.

Affected systems

Version check

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

Ubuntu94 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)
Linux2 products
  • linux≥ a8532fac7b5d27b8d62008a89593dccb6f9786ef, < 786f6314604b34c3e7de5f733f4e08e35c448a50 | ≥ a8532fac7b5d27b8d62008a89593dccb6f9786ef, < 6a32cbe95029ebe21cc08349fd7ef2a3d32d2043 | ≥ a8532fac7b5d27b8d62008a89593dccb6f9786ef, < ddf7233fcab6c247379d0928d46cc316ee122229 | 6.12
  • linux_kernel≥ 6.12, < 6.12.44 | ≥ 6.13, < 6.16.4 | 6.17:rc1 | 6.17:rc2
Debian1 product
  • linux< 6.12.48-1 | < 6.16.5-1

3 vendors · 97 products

References

7 links