VulnerabilityPublished 7 Oct 2026Updated 26 Oct 2026

CVE-2026-106114: ImageSharp · ICC CLUT parsing allocates from unvalidated channel and grid dimensions

Affects SixLabors.ImageSharpSource GCVE Database

Authoritative record:CVE-2026-106114· Medium 5.3

Not known to be exploited · CVSS 5.3 Medium : upgrade to 4.1.2 when convenient.

Data as of 26 Oct 2026, 17:16 UTC

CVSS 3.1 base score

5.3Medium

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.3% chance of exploitation in 30 days – higher than 25% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 4.1.2, 3.2.0

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: None
Scope: Unchanged
Confidentiality: None
Integrity: None
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: None: The vulnerable system can be exploited without any interaction from any user.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: None: There is no loss of confidentiality within the impacted component.
Integrity: None: There is no loss of integrity within the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 6 Oct 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponised: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 26 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponised: Public exploit code exists in Metasploit or Exploit-DB, or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade SixLabors.ImageSharp to 4.1.2; SixLabors.ImageSharp to 3.2.0.

Affected software

Product	Affected	Fixed in
NuGetSixLabors.ImageSharp	Affected >=4.0.0 <4.1.2	Fixed in 4.1.2
NuGetSixLabors.ImageSharp	Affected >=1.0.0-beta0001 <3.2.0	Fixed in 3.2.0

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

Description

### Summary A malformed embedded ICC profile can make ImageSharp allocate memory from attacker-controlled CLUT channel and grid dimensions before verifying that the declared CLUT values are present. In published v1 through v3 packages, the public lazy ICC parser allocates approximately 115 MB from the 200-byte test profile before rejecting the truncated tag. In published v4 packages, decoding with ICC conversion enabled requests an 860,934,420-byte managed float array from the same profile. ### Affected package and versions - Package: `SixLabors.ImageSharp` (NuGet) - Affected range: `>= 1.0.0-beta0001, <= 4.1.1` - Commit `0815358f9202a78bc7f3b83e19282dc3654b500f` corresponds to release **v4.1.1**. The parser defect is present from the first published NuGet prerelease, `1.0.0-beta0001`, through the latest published release, 4.1.1. The automatic `Image.Load` conversion path used by the main PoC exists in `>= 4.0.0, <= 4.1.1`; earlier versions expose the same parser defect through the public `IccProfile.Entries` accessor. ### Details The reproduced profile has an `A2B0` multi-process-elements (`mpet`) tag with a `clut` element declaring 15 input channels, 15 output channels, and three grid points per input channel. [`ReadClutF32`](https://github.com/SixLabors/ImageSharp/blob/0815358f9202a78bc7f3b83e19282dc3654b500f/src/ImageSharp/Metadata/Profiles/ICC/DataReader/IccDataReader.Lut.cs#L139-L162) computes `3^15 * 15` and allocates that many floats before reading any CLUT values or verifying that the tag has enough remaining data. The supplied 200-byte profile ends immediately after the CLUT grid descriptor. In v4, the path is reached when an application decodes an embedded ICC profile using `DecoderOptions.ColorProfileHandling = ColorProfileHandling.Convert`. The default setting, `Preserve`, does not parse the profile for conversion. In v1 through v3, `ReadClutF32` uses a jagged representation. Loading an ICC-bearing JPEG and then accessing `decoded.Metadata.IccProfile.Entries` reaches the public lazy parser. The malformed profile allocates the `3^15`-entry outer array before the missing CLUT values are detected. ### Reproduction environment and result The supplied automatic-conversion exploit and control were run against the published NuGet 4.1.1 `net8.0` DLL in Docker on Debian 12 / Linux arm64 with .NET SDK 8.0.424 and .NET runtime 8.0.30. The same conversion fixture was run against published 4.0.0 and 4.1.0 with the same result. Published 1.0.0, 2.0.0, 2.1.13, 3.0.0, and 3.1.12 were tested through public JPEG decode followed by `IccProfile.Entries`; each allocated approximately 114.9 MB, skipped the malformed tag, and exited normally. The published `1.0.0-beta0001` public `IccProfile(bytes).Entries` path allocated 114,813,528 bytes before a catchable managed bounds exception. One exploit decode increased `GC.GetTotalAllocatedBytes(true)` by approximately 861.5 million bytes, then returned `InvalidIccProfileException: Invalid conversion method`. The reader catches the truncated-tag error and drops that tag. The identical input with `ColorProfileHandling.Preserve` completed successfully with roughly 0.5 million allocated bytes in the harness. One complete exploit run produced: ```text mode=exploit profile_bytes=200 requested_float_array=215233605 requested_bytes=860934420 imagesharp_assembly=/work/bin/Release/net8.0/SixLabors.ImageSharp.dll imagesharp_version=4.1.1+0815358f9202a78bc7f3b83e19282dc3654b500f observed_exception=SixLabors.ImageSharp.Metadata.Profiles.Icc.InvalidIccProfileException: Invalid conversion method. managed_bytes_allocated=861476416 Docker exit status: 0 ``` The control from the same image produced: ```text mode=control profile_bytes=200 requested_float_array=215233605 requested_bytes=860934420 imagesharp_assembly=/work/bin/Release/net8.0/SixLabors.ImageSharp.dll imagesharp_version=4.1.1+0815358f9202a78bc7f3b83e19282dc3654b500f decoded=1x1 icc_present=True managed_bytes_allocated=511888 Docker exit status: 0 ``` The exact allocation counter includes runtime allocations and varies slightly between processes; the requested CLUT array itself is 860,934,420 bytes. No active exploitation is known. ### Impact This report demonstrates a large attacker-controlled transient allocation in the ICC conversion path. It does not demonstrate unhandled process termination: allocation failure is caught while parsing the malformed tag, so the impact should be limited to memory pressure / input-validation failure unless a reproduction demonstrates a stronger result. ### Complete PoC files Program.cs: ```csharp using System; using System.Buffers.Binary; using System.IO; using System.Reflection; using SixLabors.ImageSharp; using SixLabors.ImageSharp.Formats; using SixLabors.ImageSharp.Formats.Png; using SixLabors.ImageSharp.Metadata.Profiles.Icc; using SixLabors.ImageSharp.PixelFormats; static class Program { private const int RequestedFloats = 215233605; // 3^15 * 15 private co

CWE-789Memory Allocation with Excessive Size Value (opens in a new tab)
Variant weakness
The product allocates memory based on an untrusted, large size value, but it does not ensure that the size is within expected limits, allowing arbitrary amounts of memory to be allocated.
Implementation · Architecture and Design
Perform adequate input validation against any value that influences the amount of memory that is allocated. Define an appropriate strategy for handling requests that exceed the limit, and consider supporting a configuration option so that the administrator can extend the amount of memory to be used if necessary.
Operation
Run your program using system-provided resource limits for memory. This might still cause the program to crash or exit, but the impact to the rest of the system will be minimized.
OWASP Cheat Sheets
Abuse Case (opens in a new tab)
OWASP ASVS 4.0.3
V8.1.4 (opens in a new tab)
V13.4.1 (opens in a new tab)
V11.1.4 (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

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Affected software

Description

WeaknessesCWE-789

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