CVE-2026-105768: apko /etc/passwd and /etc/group UID/GID truncation writes package-supplied entries as root
chainguard-dev · apko
Fixed in 1.4.5 · Affected: chainguard-dev apko before 1.4.5 · Exploitation: unlikely (under 1%)
Not in CyberSIXT coverage yet: no article names this CVE. This page shows the public record.
Higher than 23% of scored CVEs
DescriptionCVE.org
apko allows users to build and publish OCI container images built from apk packages. From version 0.2.0 to before version 1.4.5, UserEntry.Parse and GroupEntry.Parse in pkg/passwd read the UID and GID fields of /etc/passwd and /etc/group entries with strconv.Atoi and convert them to uint32 without a range check. On 64-bit platforms an out-of-range value such as 4294967296 (2^32) is truncated to 0, and negative values wrap. Because apko parses the passwd and group entries supplied by the packages it installs and writes them back into the image, an attacker who controls a package installed into the image can ship an entry that appears to declare an unprivileged UID or GID but is written into the built image as UID 0 or GID 0 (root). The truncated UID is also used when resolving the image's run-as user. This issue has been fixed in version 1.4.5.
Affected products1
From the CVE record. A product or version that is not listed is unknown, not unaffected.
- chainguard-dev · apkofrom 0.2.0 before 1.4.5
On the Atlas
Every published CVE is on the CyberSIXT Atlas, grouped by weakness, vendor and month.
- Exploitation
- Unlikely (under 1%). EPSS under 1%, or no score yet.
- CISA KEV
- Not listed
- Public check
- No public nuclei template
- Vendor
- chainguard-dev
- Published
- October 2026
CoverageNo articles yet
No CyberSIXT article names CVE-2026-105768 yet, so there is no coverage timeline, action brief or change log for it. Everything on this page comes from the public CVE record, CISA KEV, EPSS and the nuclei template index. Search the archive or see the CVEs in the news.