4.9
MEDIUM CVSS 3.1
CVE-2026-55079
Coder's unbounded memory allocation in provisioner file upload allows authenticated denial of service
Description

Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.24.0 and prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, `NewDataBuilder` in `provisionersdk/proto/dataupload.go` allocated a byte slice using the client-supplied `FileSize` from a `DataUpload` message without an upper-bound check. Although the DRPC wire limit is 4 MiB, the `FileSize` value itself was unconstrained. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates `FileSize` against an upper bound (`MaxFileSize = 100 MiB`) before allocation. As a workaround, restrict access to the provisioner daemon serve endpoint to trusted provisioner daemon service accounts.

INFO

Published Date :

July 8, 2026, 12:16 a.m.

Last Modified :

July 8, 2026, 12:16 a.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-55079 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

No affected product recoded yet

CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 3.1 MEDIUM [email protected]
Solution
Update Coder to a patched version or restrict access to the provisioner daemon endpoint.
  • Update Coder to version 2.29.7 or later.
  • Restrict access to the provisioner daemon endpoint.
  • Validate FileSize against an upper bound before allocation.
References to Advisories, Solutions, and Tools
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-55079 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-55079 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-55079 vulnerability anywhere in the article.

The following table lists the changes that have been made to the CVE-2026-55079 vulnerability over time.

Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.

  • New CVE Received by [email protected]

    Jul. 08, 2026

    Action Type Old Value New Value
    Added Affected [{'vendor': 'coder', 'product': 'coder', 'versions': [{'status': 'affected', 'version': '>= 2.34.0, < 2.34.2'}, {'status': 'affected', 'version': '>= 2.33.0, < 2.33.8'}, {'status': 'affected', 'version': '>= 2.30.0, < 2.32.7'}, {'status': 'affected', 'version': '>= 2.24.0, < 2.29.17'}]}]
    Added Description Coder allows organizations to provision remote development environments via Terraform. Starting in version 2.24.0 and prior to versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2, `NewDataBuilder` in `provisionersdk/proto/dataupload.go` allocated a byte slice using the client-supplied `FileSize` from a `DataUpload` message without an upper-bound check. Although the DRPC wire limit is 4 MiB, the `FileSize` value itself was unconstrained. The fix in versions 2.29.7, 2.32.7, 2.33.8, and 2.34.2 validates `FileSize` against an upper bound (`MaxFileSize = 100 MiB`) before allocation. As a workaround, restrict access to the provisioner daemon serve endpoint to trusted provisioner daemon service accounts.
    Added CVSS V3.1 AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
    Added CWE CWE-789
    Added Reference https://github.com/coder/coder/pull/25710
    Added Reference https://github.com/coder/coder/releases/tag/v2.29.17
    Added Reference https://github.com/coder/coder/releases/tag/v2.32.7
    Added Reference https://github.com/coder/coder/releases/tag/v2.33.8
    Added Reference https://github.com/coder/coder/releases/tag/v2.34.2
    Added Reference https://github.com/coder/coder/security/advisories/GHSA-f962-qm93-mj4c
EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.