Red Hat Security Advisory: osbuild-composer security update
Affects Red Hat osbuild-composerSource GCVE Database
Mentioned vulnerabilities
Not known to be exploited · CVSS 7.5 High : upgrade Red Hat http to 1.27.2 or 1.26.9 soon.
Data as of 29 Oct 2026, 08:27 UTC
- EPSS
- 0.4% chance of exploitation in 30 days – higher than 41% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
- Patch
- Available – fixed in 1.27.2, 1.26.9
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HExploitation evidence
Disclosed: evidence found.
CVE published 8 Oct 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
Upgrade net/http to 1.27.2 or 1.26.9.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Go standard librarynet/http | Affected
| Fixed in
|
| Go standard librarynet/http | Affected
| Fixed in
|
Gonet/httppkg:golang/net/httpOther threats | Affected
| Fixed in
|
Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.
AI-suggested
Red Hat has released updated osbuild-composer packages for Red Hat Enterprise Linux 10.0 Extended Update Support that address these vulnerabilities. Users should apply these official security updates promptly following the guidance at https://access.redhat.com/articles/11258. No additional mitigations beyond applying the vendor-provided patches are indicated in the advisory.
Description
Red Hat has issued a security update for osbuild-composer, a service that builds customized OS artifacts including VM images and OSTree commits. The update addresses multiple vulnerabilities primarily involving denial of service and man-in-the-middle attack vectors in various Go language components used by osbuild-composer. These include issues in MongoDB Go Driver, gRPC-Go, golang net/http, crypto/tls, mime/multipart, HTTP/2 handling, and crypto/x509. The vulnerabilities affect Red Hat Enterprise Linux 10.0 Extended Update Support across multiple architectures.
References
- access.redhat.com/errata/RHSA-2026:91646 (opens in a new tab)
- access.redhat.com/security/updates/classification/ (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2531587 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2533175 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548334 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548336 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548341 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2548344 (opens in a new tab)
- bugzilla.redhat.com/show_bug.cgi?id=2556068 (opens in a new tab)
- security.access.redhat.com/data/csaf/v2/advisories/2026/rhsa-2026_91646.json (opens in a new tab)