vulnerability / NVI-00011707 / Revision 1
ImageSharp: ICC LUT16 output channel count can write beyond Vector4
GitHub lists this reviewed advisory for SixLabors.ImageSharp. Published version ranges and source prerequisites are shown below; this is not an inspection of a visitor’s application.
This report has not inspected your inventory, configuration, deployed build, reachability or evidence. A catalog listing and a severity score do not establish exposure or compromise.
01 / Meaning
Why it matters
Published affected context helps an owner decide what evidence to gather. This report has not examined your application.
7.5 high
GitHub source severity; exploitability and local consequence require separate evidence.
As of · GitHub Advisory Database
02 / Applicability
The affected context
Affected versions, configuration prerequisites and known exclusions are public. Confirm each one against the deployed service.
SixLabors.ImageSharp
source listed>= 4.0.0, <= 4.1.1
### Summary When ICC conversion is enabled, a malformed embedded ICC LUT16 profile with more than four output channels can corrupt memory during ImageSharp color conversion. The ICC parser accepts up to 15 CLUT output channels, while the conversion implementation stores intermediate values in `Vector4`. ### Affected package and versions - Package: `SixLabors.ImageSharp` (NuGet) - Affected published releases: **4.0.0, 4.1.0, and 4.1.1** - Affected range: `>= 4.0.0, <= 4.1.1` - Commit `0815358f9202a78bc7f3b83e19282dc3654b500f` corresponds to release **v4.1.1**. The reproduced `ColorProfileHandling.Convert` path and the unsafe `Vector4` LUT operations are present in v4.0.0 and unchanged through v4.1.1. The three-output control succeeds on all three published 4.x releases; the fifteen-output exploit terminates all three. ### Details `IccClut` accepts one through fifteen input and output channels. In the reproduced `A2B0` LUT16 path, an attacker-controlled profile declares three input channels and fifteen output channels. [`ClutCalculator.Calculate`](https://github.com/SixLabors/ImageSharp/blob/0815358f9202a78bc7f3b83e19282dc3654b500f/src/ImageSharp/ColorProfiles/Icc/Calculators/C
03 / Response
What to do next
- investigate
Identify the exact component and deployed version, examine the linked publisher’s conditions, and retain evidence of any mitigation.
Confirm current vendor support, compatibility and deployment evidence. This report has not tested a fix in your system. GitHub Advisory Database
A fixed release is not deployment evidence.
Check current vendor support and compatibility. After making a change, verify the deployed build and relevant runtime conditions. Keep the evidence, owner and time. An updated lockfile alone does not prove what is running.
04 / Limits
What this report cannot establish
- Customer inventory, deployment, reachability and exploitation have not been inspected.
05 / Provenance
Sources you can inspect
Each assertion retains its source. Mirrored records may repeat one underlying publisher; additional links are not independent corroboration.
- GHSA-ffp7-56pq-64mr ↗
GitHub Advisory Database · vendor advisory
Observed . GitHub Advisory Database; CC-BY-4.0. Each advisory links its original attribution. Null normalizes fields.
Public revision history
Only published revisions appear here. Routine fetches do not create a material-change event.
- Revision 1 ·
First indexed by Null; source disclosure date is shown separately.