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CVE.org (no NVD analysis yet)· CNA GitHub_M

CVE-2026-106115: ImageSharp: TIFF CCITT T6 encoder writes beyond an undersized output buffer

HighCVSS 7.5 · v3.1—No exploit Fix available

Noroxi assessment

Priority: Monitor (action score 30/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.38% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: SixLabors ImageSharp 4.1.2.

Low priority for now. Upgrade to SixLabors ImageSharp 4.1.2 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

ImageSharp is a 2D graphics library. From 2.1.0 until 4.1.2, the TIFF CCITT Group 4 encoder allocates Width times rowsPerStrip bytes even though T6BitCompressor.CompressStrip can emit encoded row data and two 12-bit end-of-facsimile-block codes beyond that capacity. TiffCcittCompressor.WriteCode performs unchecked writes, and a decode-and-re-encode flow can inherit TiffCompression.CcittGroup4Fax and one-bit metadata from attacker-supplied input. The resulting out-of-bounds writes can corrupt memory and terminate the process. This issue is fixed in version 4.1.2.

Published
Oct 6, 2026
Updated
Oct 24, 2026
EPSS
0.3% · 33th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
proof of concept
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
7.5
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

Follow CVE-2026-106115

When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

VendorProduct
sixlaborsimagesharp

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • SixLabors ImageSharp

    • >= 2.1.0, < 4.1.2affected

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • sixlabors imagesharp2.1.0 and later · before 3.2.0
  • sixlabors imagesharp4.0.0 and later · before 4.1.2

Package-level exposure

OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.

EcosystemPackageAffected rangeFix
NuGetSixLabors.ImageSharpfrom 2.1.0 · before 3.2.03.2.0
NuGetSixLabors.ImageSharpfrom 4.0.0 · before 4.1.24.1.2

Same product

sixlabors: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-106118ImageSharp: Tiled fax TIFF: tile buffer sized by TileWidth but fax decompressor writes scanlines of ImageWidth — heap OOB write
    30Monitor
  • CVE-2026-106117ImageSharp: CCITT fax decompression (T4/Modified Huffman): unbounded WriteBits overflows strip buffer — heap OOB write in SixLabors.ImageSharp
    30Monitor
  • CVE-2026-106113ImageSharp: HistogramEqualization uses an unvalidated luminance as an unchecked histogram index
    30Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-106112Oct 6, 2026 · ImageSharp: ICC LUT16 output channel count can write beyond Vector4
    30Monitor
  • ← EarlierCVE-2026-106114Oct 6, 2026 · ImageSharp: ICC CLUT parsing allocates from unvalidated channel and grid dimensions
    21Monitor
  • Later →CVE-2026-106116Oct 6, 2026 · ImageSharp: BigTIFF IFD count can keep a decoder thread in a non-progressing loop
    21Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
SixLabors ImageSharp4.1.2 · descriptionVendor (CNA)
NuGet:SixLabors.ImageSharp3.2.0Package registry (OSV)
NuGet:SixLabors.ImageSharp4.1.2Package registry (OSV)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. Fix recordedsame day
  3. TodayNov 13, 2026+38 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

  • CVE-2026-1061100 days apartImageSharp: TIFF CCITT T4 encoder can write past its compressed output buffer
    30Monitor
  • CVE-2026-1061120 days apartImageSharp: ICC LUT16 output channel count can write beyond Vector4
    30Monitor
  • CVE-2026-1061130 days apartImageSharp: HistogramEqualization uses an unvalidated luminance as an unchecked histogram index
    30Monitor
  • CVE-2026-1061170 days apartImageSharp: CCITT fax decompression (T4/Modified Huffman): unbounded WriteBits overflows strip buffer — heap OOB write in SixLabors.ImageSharp
    30Monitor
  • CVE-2026-1061180 days apartImageSharp: Tiled fax TIFF: tile buffer sized by TileWidth but fax decompressor writes scanlines of ImageWidth — heap OOB write
    30Monitor

Not on record for this CVE: researcher credit · public bounty program.

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
none
Integrity
none
Availability
high · the service can be disrupted
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
None
Integrity impact
None
Availability impact
High

Weakness class (CWE)

CWE-787 · Out-of-bounds Write

CVSS vector

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

nvd-secondary

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

MITRE has no CAPEC/ATT&CK mapping for this CWE.

Change log

  1. SSVC exploitation— → poc
  2. Exploit maturity— → none
  3. Fix✗ → ✓

For records you follow, these changes also arrive as notifications. →

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records