Quick answer
Direct answer
Risk scores
| CVSS metric | What it means |
|---|---|
| Attack vector (AV:L) | Local access needed |
| Attack complexity (AC:L) | Low complexity |
| Privileges required (PR:L) | Low privileges required |
| User interaction (UI:R) | A user must take an action |
| Scope (S:U) | Scope unchanged |
| Confidentiality (C:H) | High confidentiality impact |
| Integrity (I:H) | High integrity impact |
| Availability (A:H) | High availability impact |
CVSS:3.1/AV:L/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
About Redhat Enterprise Linux
CVE-2026-42169 affects Redhat Enterprise Linux, a product from Redhat. Before acting, confirm where Redhat Enterprise Linux runs in your estate, who owns it and whether it is reachable from the internet, because exposure decides real risk more than the score alone.
What the flaw is
In plain terms: A heap-buffer-overflow vulnerability exists in the APNG (Animated PNG) file loader of GIMP. This flaw occurs when the `fcTL` width exceeds the `IHDR` width, leading to pixel data being written past the end of a heap allocation. Additionally, a heap-based buffer overflow exists in the DDS plug-in due to a BPP mismatch in the `load_layer()` function. Both vulnerabilities can be triggered by opening a specially crafted image file, potentially leading to code execution.
Based on its CVSS vector, the flaw needs local or adjacent access, needs some level of access, and relies on a user taking an action. Apply the vendor fix and confirm exposure on internet facing and business critical assets first.
Affected versions and timeline
| Field | Detail |
|---|---|
| Product | Redhat Enterprise Linux |
| Affected versions | Enterprise Linux 9.0; Enterprise Linux Eus 9.6 |
| Published | Aug 4, 2026 |
| Last modified | Oct 12, 2026 |
| Added to CISA KEV | Not listed |
| Assigning CNA | secalert@redhat.com |
How to detect it
- Inventory every instance of Redhat Enterprise Linux and record the running version against the affected range above.
- Check external attack surface scans for internet facing instances of the component.
- Review logs on affected systems for unusual requests, errors or new processes around the vulnerable function.
- Confirm with an authenticated vulnerability scan once your scanner has a check for this CVE.
How to fix it
- Apply the fixed version of Redhat Enterprise Linux named in the vendor advisory.
- If patching must wait, restrict network access to the affected service and put it behind authentication or a web application firewall rule.
- Rescan after the change to prove the exposure is gone, then close the ticket.
CTEM action plan
| CTEM stage | What to do for this CVE |
|---|---|
| Scope | Add every business service that depends on Redhat Enterprise Linux to the current CTEM cycle. |
| Discover | Find all instances, including shadow and cloud deployments, and record versions and exposure. |
| Prioritize | Rank using EPSS and CVSS together with asset exposure and business impact. |
| Validate | Confirm the flaw is reachable and exploitable in your environment and that compensating controls work. |
| Mobilize | Assign the fix to the asset owner with a due date matched to the priority, then verify closure. |
CWE References
Technical References
Frequently asked questions
Related CVEs
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