5.7

CVE-2026-97029: Flatpak: flatpak: sandboxed app can signal unsandboxed processes in the same process group

Awaiting analysis
AliasesUBUNTU-CVE-2026-97029DEBIAN-CVE-2026-97029
Published 29-09-2026Last modified 29-09-2026

Vulnerability summary

CVE-2026-97029 is a medium (CVSS 5.7) vulnerability in flatpak. EPSS estimates a 0.24% chance of exploitation in the next 30 days, higher than 14.7% of scored vulnerabilities.

Overall risk
23/100
0100
Low · default modelHow is this calculated?
CVSS score
5.7/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.24%
0%100%
Low · Change unavailable
KEVNot listedNot listed by any tracked catalog.
RansomwareNot flaggedNo ransomware use recorded.
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 2 · Related 1
MGASA-2026-0477OPENSUSE-SU-2026:11918-1

Timeline

  1. 29-09-2026
    PublishedVulnerability first disclosed.
  2. 29-09-2026
    Last modifiedVulnerability information updated.

Description

Flatpak's process ID namespace separation does not prevent a sandboxed app's kill(0, signal) or killpg(0, signal) calls from reaching processes outside the sandbox that share the same process group. A malicious or compromised Flatpak app can use this to cause denial of service by terminating processes outside its sandbox, such as the desktop shell.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.24%

Chance of exploitation in the next 30 days

Percentile

15%

Versus all other CVEs

30-day change

Change unavailable

Change unavailable

29-09-202622-10-2026

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

Debian1 product
  • flatpakAll versions (No fix recorded) | < 1.16.6-1~deb13u3 | < 1.18.4-1
Ubuntu1 product
  • flatpakAll versions (No fix recorded)

2 vendors · 2 products

References

6 links