CVE-2026-19730: Red Hat Enterprise Linux 10 Vulnerability

Description

The 'podman quadlet install --replace' command opens the existing destination file with O_CREATE|O_WRONLY but omits O_TRUNC. When the initial reflink copy attempt fails (common on non-reflink-capable filesystems including many RHEL default XFS configurations), the fallback in ReflinkOrCopy uses io.Copy which performs a non-truncating write. If the original Quadlet is larger than the new Quadlet, the file is not truncated and content from the original is preserved. The command completes with no warning. There is no risk of information leakage as the user already had access to the Quadlet in order to replace it, and in most cases, this would only lead to invalid Quadlet files. However, security-related options from the end of the old Quadlet could be included in the new Quadlet, and if the truncation resulted in a valid Quadlet file, this could result in undesirable behavior. For example, running podman quadlet install --replace to remove a single line from the end of a Quadlet - including security-sensitive content, like AddCapability - will fail, and the option will continue to be used. Further, with Volume Quadlets, this can include additional mounts which can cause content to be unintentionally exposed into containers. If, later, the image is updated then compromised content might be leaked to an attacker. The vulnerable code paths are in pkg/domain/infra/abi/quadlet.go (lines 338-360, O_CREATE|O_WRONLY without O_TRUNC) and vendor/go.podman.io/storage/pkg/fileutils/reflink_linux.go (lines 12-19, non-truncating io.Copy fallback).

Metrics

CVSS 3.1

4.2/10

CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:U/C:L/I:L/A:L

EPSS Probability

0.11%

1.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-459

Affected Software

Source: CNA advisory (CVE.org). NVD analysis pending.

Vendor	Product	Versions
Red Hat	Red Hat Enterprise Linux 10	All versions
Red Hat	Red Hat Enterprise Linux 9	All versions
Red Hat	Red Hat Hardened Images	All versions

References

Timeline

Published: Aug 13, 2026
Last Modified: Aug 14, 2026
Status: Awaiting Analysis

Frequently Asked Questions

What is CVE-2026-19730?

The 'podman quadlet install --replace' command opens the existing destination file with O_CREATE|O_WRONLY but omits O_TRUNC. When the initial reflink copy attempt fails (common on non-reflink-capable filesystems including many RHEL default XFS configurations), the fallback in ReflinkOrCopy uses io.Copy which performs a non-truncating write. If the original Quadlet is larger than the new Quadlet, the file is not truncated and content from the original is preserved. The command completes with no warning. There is no risk of information leakage as the user already had access to the Quadlet in order to replace it, and in most cases, this would only lead to invalid Quadlet files. However, security-related options from the end of the old Quadlet could be included in the new Quadlet, and if the truncation resulted in a valid Quadlet file, this could result in undesirable behavior. For example, running podman quadlet install --replace to remove a single line from the end of a Quadlet - including security-sensitive content, like AddCapability - will fail, and the option will continue to be used. Further, with Volume Quadlets, this can include additional mounts which can cause content to be unintentionally exposed into containers. If, later, the image is updated then compromised content might be leaked to an attacker. The vulnerable code paths are in pkg/domain/infra/abi/quadlet.go (lines 338-360, O_CREATE|O_WRONLY without O_TRUNC) and vendor/go.podman.io/storage/pkg/fileutils/reflink_linux.go (lines 12-19, non-truncating io.Copy fallback).

How severe is CVE-2026-19730?

CVE-2026-19730 has a CVSS score of 4.2/10 (MEDIUM severity). The EPSS model estimates a 0.11% probability of exploitation in the next 30 days.

How do I fix CVE-2026-19730?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

How Strix Helps

Related CVEs from 2026

View all 2026CVEs →