5.5

CVE-2025-21834: seccomp: passthrough uretprobe systemcall without filtering

Analyzed
AliasesUBUNTU-CVE-2025-21834DEBIAN-CVE-2025-21834
Published 06-03-2025Last modified 11-05-2026

Vulnerability summary

CVE-2025-21834 is a medium (CVSS 5.5) vulnerability in linux. EPSS estimates a 0.18% chance of exploitation in the next 30 days, higher than 7.6% of scored vulnerabilities.

Priority
Routine

Not severe (CVSS 5.5, local access); no exploitation reported by the 5 checked sources

Source freshness unavailable

How is this decided?
CVSS score
5.5/10
010
Medium · v3.1 (NVD)
EPSS score
0.18%
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 4 · Related 5
RHSA-2026:61887USN-7379-1USN-7381-1USN-7382-1USN-7379-2USN-7380-1

Timeline

  1. 06-03-2025
    PublishedVulnerability first disclosed.
  2. 11-05-2026
    Last modifiedVulnerability information updated.

Description

In the Linux kernel, the following vulnerability has been resolved: seccomp: passthrough uretprobe systemcall without filtering When attaching uretprobes to processes running inside docker, the attached process is segfaulted when encountering the retprobe. The reason is that now that uretprobe is a system call the default seccomp filters in docker block it as they only allow a specific set of known syscalls. This is true for other userspace applications which use seccomp to control their syscall surface. Since uretprobe is a "kernel implementation detail" system call which is not used by userspace application code directly, it is impractical and there's very little point in forcing all userspace applications to explicitly allow it in order to avoid crashing tracked processes. Pass this systemcall through seccomp without depending on configuration. Note: uretprobe is currently only x86_64 and isn't expected to ever be supported in i386. [kees: minimized changes for easier backporting, tweaked commit log]

CVSS metrics

3 scores · 3 sources · 1 version

EPSS trend

Probability

0.18%

Chance of exploitation in the next 30 days

Percentile

8%

Versus all other CVEs

30-day change

No change 0.00 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

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.

Ubuntu79 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≥ ff474a78cef5cb5f32be52fe25b78441327a2e7c, < 5a262628f4cf2437d863fe41f9d427177b87664c | ≥ ff474a78cef5cb5f32be52fe25b78441327a2e7c, < fa80018aa5be10c35e9fa896b7b4061a8dce3eed | ≥ ff474a78cef5cb5f32be52fe25b78441327a2e7c, < cf6cb56ef24410fb5308f9655087f1eddf4452e6 | 6.11
  • linux_kernel≥ 6.11, < 6.12.14 | ≥ 6.13, < 6.13.3 | 6.14:rc1
Debian1 product
  • linux< 6.12.15-1

3 vendors · 82 products

References

12 links
Show all 12 references