Red Hat Security Advisory: flatpak-builder security update
Affects Red Hat flatpak-builderSource GCVE Database
Not known to be exploited · CVSS 7.8 High.
Data as of 29 Oct 2026, 07:44 UTC
Thin evidence
One scorer or none| CNA (redhat) | CVSS 3.1 | 7.8 |
|---|
- EPSS
- 0.2% chance of exploitation in 30 days – higher than 21% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:HExploitation evidence
Disclosed: evidence found.
CVE published 17 Sep 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 29 Oct 2026.
What to do
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Red Hat Enterprise Linux 10flatpak-builder | Affected– | Fixed in– |
| Red Hat Enterprise Linux 10.0 Extended Update Supportflatpak-builder | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8flatpak-builder | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Supportflatpak-builder | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-Onflatpak-builder | Affected– | Fixed in– |
| Red Hat Enterprise Linux 8.8 Telecommunications Update Serviceflatpak-builder | Affected– | Fixed in– |
AI-suggested
Red Hat has released a security update for flatpak-builder that addresses this vulnerability. Users of Red Hat Enterprise Linux 9 and its variants should apply the update to flatpak-builder version 1.2.3-1.el9_8.1 or later as provided in the Red Hat advisory RHSA-2026:80496. Detailed instructions for applying the update are available at https://access.redhat.com/articles/11258. No additional mitigation steps are indicated beyond applying the official patch.
Description
A security vulnerability (CVE-2026-86320) affecting flatpak-builder, a tool for building flatpaks from sources, allows host code execution via the execution of a 'git am' hook during patch source extraction when using the 'use-git-am' option. This vulnerability has been rated as important by Red Hat Product Security and affects Red Hat Enterprise Linux 9 and its variants. A security update is available to address this issue.