7.8

CVE-2025-38177: sch_hfsc: make hfsc_qlen_notify() idempotent

Modified
AliasesUBUNTU-CVE-2025-38177DEBIAN-CVE-2025-38177
Published 04-07-2025Last modified 05-08-2026

Vulnerability summary

CVE-2025-38177 is a high (CVSS 7.8) Incomplete Cleanup vulnerability in debian debian_linux. EPSS estimates a 0.21% chance of exploitation in the next 30 days, higher than 11.4% 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
0.21%
0%100%
Low · +0.02 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 99 · Related 86
DLA-4271-1DLA-4327-1OPENSUSE-SU-2025:20081-1RHSA-2025:14413RHSA-2025:14511RHSA-2025:14691

Timeline

  1. 04-07-2025
    PublishedVulnerability first disclosed.
  2. 05-08-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: sch_hfsc: make hfsc_qlen_notify() idempotent hfsc_qlen_notify() is not idempotent either and not friendly to its callers, like fq_codel_dequeue(). Let's make it idempotent to ease qdisc_tree_reduce_backlog() callers' life: 1. update_vf() decreases cl->cl_nactive, so we can check whether it is non-zero before calling it. 2. eltree_remove() always removes RB node cl->el_node, but we can use RB_EMPTY_NODE() + RB_CLEAR_NODE() to make it safe.

CVSS metrics

5 scores · 4 sources · 2 versions

EPSS trend

Probability

0.21%

Chance of exploitation in the next 30 days

Percentile

11%

Versus all other CVEs

30-day change

Increase +0.02 pp

From 0.19% 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.

Ubuntu141 products
  • linux< 4.15.0-239.251 | < 5.4.0-219.239 | < 5.15.0-143.153 | < 6.8.0-63.66
  • linux-allwinner-5.19All versions (No fix recorded)
  • linux-aws< 4.15.0-1182.195 | < 5.4.0-1148.158 | < 5.15.0-1087.94 | < 6.8.0-1031.33
  • linux-aws-5.0All versions (No fix recorded)
  • linux-aws-5.11All versions (No fix recorded)
Debian2 products
Linux2 products
  • linux≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < 9a5fd5c2f4d4afdd5e405083ee53e0789ce76956 | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < 72c61ffbeeb8c50f6d4d70c65d3283aa1bac57a7 | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < a5efc95a33bd4fcb879250852828cc58c7862970 | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < 0475c85426b18eccdcb7f9fb58d8f8e9c6c58c87 | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < 9030a91235ae4845ec71902c3e0cecfc9ed1f2df | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < d06476714d2819b550e0cc39222347e2c8941c9d | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < c1175c4ad01dbc9c979d099861fa90a754f72059 | ≥ 959466588aa7f84ccf79ae36a1d89542eaf9aaec, < 51eb3b65544c9efd6a1026889ee5fb5aa62da3bb | 4.14
  • linux_kernel< 5.4.297 | ≥ 5.5, < 5.10.241 | ≥ 5.11, < 5.15.190 | ≥ 5.16, < 6.1.138 | ≥ 6.2, < 6.6.90 | ≥ 6.7, < 6.12.28 | ≥ 6.13, < 6.14.6 | 6.15:rc1

3 vendors · 145 products

References

24 links
Show all 24 references