How severe is CVE-2026-39817?

CVE-2026-39817 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.

Is CVE-2026-39817 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-39817?

CVE-2026-39817 affects Golang Go. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-39817?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2026-39817 have an EU (EUVD) identifier?

Yes. CVE-2026-39817 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28421.

When was CVE-2026-39817 published?

CVE-2026-39817 was published on 2026-05-07 and last updated on 2026-06-17.

CVE-2026-39817

CVE-2026-39817 is a medium-severity vulnerability in Golang Go with a CVSS 3.x base score of 5.9. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-787.

Key facts

Severity: Medium (CVSS 3.x base score 5.9)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-28421
Weakness: CWE-787
Affected product: Golang Go
Published: 2026-05-07
Last modified: 2026-06-17

Description

The "go tool pack" subcommand (usually used only by the compiler as an internal tool with known-good inputs) does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem.

Frequently asked questions

What is CVE-2026-39817?: The "go tool pack" subcommand (usually used only by the compiler as an internal tool with known-good inputs) does not sanitize output filenames. Extracting a malicious archive file with the "pack" subcommand can write files to arbitrary locations on the filesystem.
How severe is CVE-2026-39817?: CVE-2026-39817 has a CVSS 3.x base score of 5.9, rated medium severity. It is exploitable over local access with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is none, integrity high, and availability none.
Is CVE-2026-39817 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-39817?: CVE-2026-39817 affects Golang Go. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-39817?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-39817 have an EU (EUVD) identifier?: Yes. CVE-2026-39817 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-28421.
When was CVE-2026-39817 published?: CVE-2026-39817 was published on 2026-05-07 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:golang:go:*:*:*:*:*:*:*:*

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