# CVE-2026-55079: Coder's unbounded memory allocation in provisioner file upload allows authenticated denial of service > Authenticated attackers can cause denial of service in Coder by triggering unbounded memory allocation during file uploads. - **Severity:** Medium 4.9 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H`) - **Exploited in the wild:** Not known - **Login needed:** An administrator - **Attackable:** Over the internet - **Victim action needed:** Not needed - **Fix available:** Yes - **Published:** 7 Jul 2026 - **Updated:** 8 Jul 2026 - **Also known as:** GHSA-f962-qm93-mj4c, GO-2026-5911 ## What is CVE-2026-55079? CVE-2026-55079 is a medium-severity denial of service vulnerability in coder, published on 7 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim. ### Official 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. Weakness: CWE-789 (Memory Allocation with Excessive Size Value) ## Which versions are affected by CVE-2026-55079? 10 open source packages ship an affected version, including github.com/coder/coder/v2 and github.com/coder/coder. It affects 1 product. | Package | Ecosystem | Affected | Fixed in | | --- | --- | --- | --- | | `github.com/coder/coder/v2` | Go | From 2.24.0 | 2.29.17, 2.32.7, 2.33.8, 2.34.2 | | `github.com/coder/coder/v2` | Go | From 2.24.0 | 2.29.17 | | `github.com/coder/coder/v2` | Go | From 2.24.0 | 2.29.17 | | `github.com/coder/coder/v2` | Go | From 2.30.0 | 2.32.7 | | `github.com/coder/coder/v2` | Go | From 2.30.0 | 2.32.7 | | `github.com/coder/coder/v2` | Go | From 2.33.0 | 2.33.8 | | `github.com/coder/coder/v2` | Go | From 2.33.0 | 2.33.8 | | `github.com/coder/coder/v2` | Go | From 2.34.0 | 2.34.2 | | `github.com/coder/coder/v2` | Go | From 2.34.0 | 2.34.2 | | `github.com/coder/coder` | Go | All versions | None | Products: Coder Coder. ## How do I fix CVE-2026-55079? Upgrade github.com/coder/coder/v2 to a fixed version for your release line: 2.29.17, 2.32.7, 2.33.8 or 2.34.2. ## Is CVE-2026-55079 being exploited? There is no known exploitation of CVE-2026-55079 in the wild and no public exploit code. ## Other vulnerabilities in coder - [CVE-2026-46354](https://insights.sbomify.com/CVE-2026-46354/): Coder: PKCS#7 signature bypass in Azure instance identity allows unauthenticated agent token theft (critical 9.1) - [CVE-2026-55429](https://insights.sbomify.com/CVE-2026-55429/): Coder's workspace app upsert allows cross-workspace agent rebinding via user-controlled app ID (high 8.7) - [CVE-2026-55427](https://insights.sbomify.com/CVE-2026-55427/): Coder vulnerable to SSH config injection via unsanitized server-supplied values in `coder config-ssh` (high 8.3) - [CVE-2026-55428](https://insights.sbomify.com/CVE-2026-55428/): Coder: Route hijacking through lack of validation of agent-supplied AllowedIPs in tailnet coordinator (high 8.2) - [CVE-2024-27918](https://insights.sbomify.com/CVE-2024-27918/): Coder's OIDC authentication allows email with partially matching domain to register (high 8.2) ## Fix prompt for AI coding agents ```text Check this codebase for CVE-2026-55079 and fix it if it is affected. What it is: CVE-2026-55079 is a medium-severity denial of service vulnerability in coder, published on 7 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim. Exploitation: There is no known exploitation of CVE-2026-55079 in the wild and no public exploit code. Affected packages and fixed versions: - github.com/coder/coder/v2 (Go): affected from 2.24.0; fixed in 2.29.17, 2.32.7, 2.33.8, 2.34.2 - github.com/coder/coder/v2 (Go): affected from 2.24.0; fixed in 2.29.17 - github.com/coder/coder/v2 (Go): affected from 2.24.0; fixed in 2.29.17 - github.com/coder/coder/v2 (Go): affected from 2.30.0; fixed in 2.32.7 - github.com/coder/coder/v2 (Go): affected from 2.30.0; fixed in 2.32.7 - github.com/coder/coder/v2 (Go): affected from 2.33.0; fixed in 2.33.8 - github.com/coder/coder/v2 (Go): affected from 2.33.0; fixed in 2.33.8 - github.com/coder/coder/v2 (Go): affected from 2.34.0; fixed in 2.34.2 - github.com/coder/coder/v2 (Go): affected from 2.34.0; fixed in 2.34.2 - github.com/coder/coder (Go): affected all versions; no fix listed Task: 1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies. 2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it. 3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead. 4. Run the tests and summarise what changed and why. 5. If nothing in the project is affected, say so and change nothing. Reference: https://insights.sbomify.com/CVE-2026-55079/ (Markdown: https://insights.sbomify.com/CVE-2026-55079/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2026-55079 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-55079 - OSV: https://osv.dev/vulnerability/CVE-2026-55079 --- From sbomify Insights: https://insights.sbomify.com/CVE-2026-55079/ Summaries are generated and may contain mistakes; the official description above is the record.