How severe is CVE-2026-71493?

No CVSS score has been assigned to CVE-2026-71493 yet. Review the advisory details and affected package list to assess your exposure.

Which packages are affected by CVE-2026-71493?

CVE-2026-71493 affects the following packages: github.com/infracost/infracost (Go). Ecosystems affected: Go.

How do I fix CVE-2026-71493?

Update github.com/infracost/infracost to 0.10.45 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-71493 is resolved across your whole dependency graph.

How do I detect CVE-2026-71493 in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/infracost/infracost, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2026-71493 if there is no patch (or I can't update yet)?

Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Is CVE-2026-71493 actively exploited in the wild?

No public exploit code has been indexed for CVE-2026-71493 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2026-71493?

CVE-2026-71493 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 45th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2026-71493?

CVE-2026-71493 is classified as Path Traversal (CWE-22), CWE-59 (CWE-59). These weakness types describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2026-71493 published, and has it been updated?

CVE-2026-71493 was published on August 21, 2026 and was last updated on October 21, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

🐹 Go

Not in CISA KEV

CVE-2026-71493 — infracost

Fix: infracost/infracost@4d39331

CVE-2026-71493 is a Path Traversal vulnerability in github.com/infracost/infracost. A fix is available for github.com/infracost/infracost — see the affected versions and patch details below.

Infracost: Arbitrary file read via config-template readFile symlink traversal

Also known asGHSA-mmg6-4qmv-6pc8GO-2026-6439

Published

Aug 21, 2026

Updated

Oct 21, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 25, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

No confirmed exploitation observed yet

A successful exploit gives an attacker total control of the affected component, not partial access.
CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.

Exploitation and automatability from CISA’s SSVC triage for CVE-2026-71493.

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs45th percentile — riskier than 45% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

Real-World Exposure

1 pkg affected

🐹github.com/infracost/infracost

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Go packages — download data is not available via public APIs for these ecosystems.

Description

Impact

Path traversal via link following in the Infracost config-template parser. The readFile, pathExists, isDir, and matchPaths template functions confined repo-supplied paths with a lexical filepath.Rel check plus a leaf-only os.Lstat:

{{ readFile "evil/file" }}

With an intermediate directory symlink committed in the repo (evil -> /), the path is lexically clean and the leaf is a regular file, so both checks pass, but os.ReadFile follows the symlink and reads outside the checkout. The contents are rendered into the generated config and surfaced via the Infracost dashboard and PR comment, so anyone who can open a pull request can read files off the runner.

Affects infracost up to and including v0.10.44. Successful exploitation reads any file the CLI process can reach on the runner. Impact depends on what the run exposes: under on: pull_request (the configuration in Infracost's documentation) fork pull requests run without secrets and with a read-only token, so exposure is limited. If Infracost runs under pull_request_target, or is triggered by a same-repository pull request, the read reaches the repository's secrets, enabling secret theft. The patch confines all four functions regardless of trigger.

Patches

Fixed in v0.10.45 (#3586) by routing all four functions through security.IsPathAllowed, which resolves symlinks anywhere in the path before a segment-aware containment check. The same fix landed in config#14 and parser#144.

Installed via the official script, a package manager, or the latest Docker tag: upgrade to v0.10.45 (or later) to receive the fix.
Pinned to a specific version or image digest: bump to v0.10.45.

Workarounds

No full fix without upgrading. To limit exposure: run Infracost under on: pull_request rather than pull_request_target, and keep fork pull requests from receiving secrets (the defaults).

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/infracost/infracost`	all versions	0.10.45`go get github.com/infracost/infracost@v0.10.45`

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/infracost/infracost, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update github.com/infracost/infracost to 0.10.45 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-71493 is resolved across your whole dependency graph.
Workarounds
Resolve every user-supplied path to its canonical form and reject anything that escapes the intended directory, and run the component under an account that has no read or write access outside the directory it legitimately serves.

Frequently Asked Questions

### Impact Path traversal via link following in the Infracost config-template parser. The `readFile`, `pathExists`, `isDir`, and `matchPaths` template functions confined repo-supplied paths with a lexical `filepath.Rel` check plus a leaf-only `os.Lstat`: ``` {{ readFile "evil/file" }} ``` With an intermediate directory symlink committed in the repo (`evil -> /`), the path is lexically clean and the leaf is a regular file, so both checks pass, but `os.ReadFile` follows the symlink and reads outside the checkout. The contents are rendered into the generated config and surfaced via the Infraco