CVE-2024-25269

What it actually does

Memory leak in JpegEncoder::Encode allows repeated allocation without release, leading to unbounded heap growth and eventual process termination under sustained load.

Why it matters to the business

Systems that decode or encode images from untrusted sources can experience denial of service through memory exhaustion, interrupting services and requiring restarts; the flaw affects widely deployed packages in cloud Linux environments with a long window since disclosure.

How an attack unfolds

An attacker repeatedly submits specially crafted image data to any application linked against the vulnerable libheif library; each call to the encoder leaks memory until the target process or host becomes unresponsive.

How to fix it

Upgrade the affected linux-aws-5.4 package to version 5.4.0-1135.145~18.04.1 or later on all Ubuntu 18.04 LTS instances; rebuild or redeploy any containers or images that embed the vulnerable library.

How to confirm the fix worked

Confirm the installed package version matches or exceeds the fixed release; run regression tests that exercise JPEG encoding paths with high-volume input and verify stable memory usage.

Typical attack path

1. Identify an endpoint or service that accepts image input processed by libheif
2. Craft or mutate image payloads that exercise the JpegEncoder::Encode path
3. Send the payloads in rapid succession from one or more sources
4. Monitor until memory pressure causes the process or system to crash or throttle

How to detect it

Correlate image-processing service logs with OS-level memory metrics; look for sustained increases in resident set size of processes that call libheif encoding functions without corresponding workload growth.

What your security team should do

• Apply the listed package update immediately on all exposed Ubuntu 18.04 systems
• Add memory-usage and process-crash alerts for image-processing workloads
• Review and restrict image upload surfaces until patches are deployed