CVE-2026-39817

MEDIUMNVD 5.95.9—
EchelonGraph scoreMEDIUM confidence

Score 5.9 from GitHub Security Advisory published 2026-05-07. NVD baseline CVSS 5.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, nvd
5.9EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 5.9Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

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.

CVSS v3
5.9
EG Score
5.9MEDIUMmedium confidence
EG Risk
27
EG Risk 27/100

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity59% × 45%
Exploitation0% × 40%
Automatability0% × 15%
EPSS PROB
0.2%
EPSS %ILE
4th
KEV
Not listed

Published

May 7, 2026

Last Modified

May 13, 2026

Advisory Details (4)

Auto-updated Jun 14, 2026
Patch available.
generic

GO-2026-4979 - Go Packages

https://pkg.go.dev/vuln/GO-2026-4979
generic
https://groups.google.com/g/golang-announce/c/qcCIEXso47M
generic

cmd/go: go tool pack does not sanitize output paths · Issue #78778 · golang/go · GitHub

https://go.dev/issue/78778
generic
https://go.dev/cl/767520

Vendor Advisories for CVE-2026-39817(12)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(2)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
redhatmulticluster-engine/hypershift-addon-rhel9-operator:17869120062026-08-19redhat
redhatoadp/oadp-velero-rhel9:17840588222026-07-22redhat

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(6 across 5 ecosystems)
Debian:14(2)
PackageVulnerable rangeFix by version rangeDependents
golang-1.251.25.0-1 ... 1.25.9-1 (11 versions)
  • every version up to 1.25.10-1: fixed in 1.25.10-1
—
golang-1.261.26.0-1 ... 1.26~rc3-2 (9 versions)
  • every version up to 1.26.3-1: fixed in 1.26.3-1
—
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
golang-1.151.15.15-1 ... 1.15.9-6 (10 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
golang-1.191.19.10-1 ... 1.19.9-1 (12 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
golang-1.241.24.12-1 ... 1.24.9-1 (10 versions)
  • every version on: no fix on record
—
Go(1)
PackageVulnerable rangeFix by version rangeDependents
toolchain—
  • every version up to 1.25.10: fixed in 1.25.10
  • 1.26.0-0 up to 1.26.3: fixed in 1.26.3
—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 7× in last 7d / 27× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

Showing the most recent 100 of 224 total refreshes for this CVE.

  1. 2026-10-10 20:00 UTCEPSS rescore
  2. 2026-10-09 20:07 UTCEPSS rescore
  3. 2026-10-08 17:12 UTCEPSS rescore
  4. 2026-10-07 23:48 UTCEPSS rescore
  5. 2026-10-06 15:17 UTCEPSS rescore
  6. 2026-10-05 17:43 UTCEPSS rescore
  7. 2026-10-04 23:22 UTCEPSS rescore
  8. 2026-10-03 14:25 UTCEPSS rescore
  9. 2026-10-01 19:49 UTCEPSS rescore
  10. 2026-09-30 15:03 UTCEPSS rescore
  11. 2026-09-30 08:41 UTCOSV refresh
  12. 2026-09-28 13:51 UTCEPSS rescore
  13. 2026-09-27 13:48 UTCEPSS rescore
  14. 2026-09-26 15:58 UTCEPSS rescore
  15. 2026-09-26 00:26 UTCEPSS rescore
  16. 2026-09-20 20:15 UTCEPSS rescore
  17. 2026-09-18 19:28 UTCEPSS rescore
  18. 2026-09-18 19:28 UTCEPSS rescore
  19. 2026-09-17 19:30 UTCEPSS rescore
  20. 2026-09-16 14:08 UTCEPSS rescore
  21. 2026-09-16 05:15 UTCEPSS rescore
  22. 2026-09-15 03:11 UTCEPSS rescore
  23. 2026-09-13 16:47 UTCEPSS rescore
  24. 2026-09-12 15:01 UTCEPSS rescore
  25. 2026-09-11 15:23 UTCOSV refresh
Show 75 more
  1. 2026-09-11 14:53 UTCEPSS rescore
  2. 2026-09-11 09:37 UTCEPSS rescore
  3. 2026-09-10 09:34 UTCEPSS rescore
  4. 2026-09-08 22:00 UTCEPSS rescore
  5. 2026-09-07 16:01 UTCEPSS rescore
  6. 2026-09-06 13:47 UTCEPSS rescore
  7. 2026-09-04 05:06 UTCEPSS rescore
  8. 2026-09-02 14:12 UTCEPSS rescore
  9. 2026-09-01 13:53 UTCEPSS rescore
  10. 2026-08-30 19:17 UTCEPSS rescore
  11. 2026-08-30 01:22 UTCEPSS rescore
  12. 2026-08-28 21:41 UTCEPSS rescore
  13. 2026-08-27 14:25 UTCEPSS rescore
  14. 2026-08-26 14:46 UTCEPSS rescore
  15. 2026-08-25 13:49 UTCEPSS rescore
  16. 2026-08-23 19:33 UTCEG score recompute
  17. 2026-08-23 19:33 UTCVendor advisory
  18. 2026-08-23 19:33 UTCGHSA enrichment
  19. 2026-08-23 00:19 UTCEPSS rescore
  20. 2026-08-21 23:49 UTCEPSS rescore
  21. 2026-08-20 22:55 UTCEPSS rescore
  22. 2026-08-19 17:03 UTCEPSS rescore
  23. 2026-08-18 13:48 UTCEPSS rescore
  24. 2026-08-17 13:47 UTCEPSS rescore
  25. 2026-08-17 12:43 UTCEG score recompute
  26. 2026-08-17 12:43 UTCVendor advisory
  27. 2026-08-17 12:43 UTCGHSA enrichment
  28. 2026-08-16 14:56 UTCEPSS rescore
  29. 2026-08-16 04:43 UTCEG score recompute
  30. 2026-08-16 04:43 UTCVendor advisory
  31. 2026-08-16 04:43 UTCGHSA enrichment
  32. 2026-08-16 02:14 UTCEPSS rescore
  33. 2026-08-15 02:25 UTCEG score recompute
  34. 2026-08-15 02:25 UTCVendor advisory
  35. 2026-08-15 02:25 UTCGHSA enrichment
  36. 2026-08-15 01:30 UTCEPSS rescore
  37. 2026-08-14 03:18 UTCEG score recompute
  38. 2026-08-14 03:18 UTCVendor advisory
  39. 2026-08-14 03:18 UTCGHSA enrichment
  40. 2026-08-13 22:00 UTCEPSS rescore
  41. 2026-08-12 23:40 UTCEG score recompute
  42. 2026-08-12 23:40 UTCVendor advisory
  43. 2026-08-12 23:40 UTCGHSA enrichment
  44. 2026-08-12 13:51 UTCEPSS rescore
  45. 2026-08-12 00:33 UTCEG score recompute
  46. 2026-08-12 00:33 UTCVendor advisory
  47. 2026-08-12 00:33 UTCGHSA enrichment
  48. 2026-08-11 13:43 UTCEPSS rescore
  49. 2026-08-11 01:24 UTCEG score recompute
  50. 2026-08-11 01:24 UTCVendor advisory
  51. 2026-08-11 01:24 UTCGHSA enrichment
  52. 2026-08-11 00:00 UTCEPSS rescore
  53. 2026-08-10 01:36 UTCEG score recompute
  54. 2026-08-10 01:36 UTCVendor advisory
  55. 2026-08-10 01:36 UTCGHSA enrichment
  56. 2026-08-09 13:46 UTCEPSS rescore
  57. 2026-08-09 02:29 UTCEG score recompute
  58. 2026-08-09 02:29 UTCVendor advisory
  59. 2026-08-09 02:29 UTCGHSA enrichment
  60. 2026-08-08 16:37 UTCEPSS rescore
  61. 2026-08-07 20:29 UTCEG score recompute
  62. 2026-08-07 20:29 UTCVendor advisory
  63. 2026-08-07 20:29 UTCGHSA enrichment
  64. 2026-08-06 21:21 UTCEG score recompute
  65. 2026-08-06 21:21 UTCVendor advisory
  66. 2026-08-06 21:21 UTCGHSA enrichment
  67. 2026-08-06 13:46 UTCEPSS rescore
  68. 2026-08-05 22:13 UTCEG score recompute
  69. 2026-08-05 22:13 UTCVendor advisory
  70. 2026-08-05 22:13 UTCGHSA enrichment
  71. 2026-08-05 19:17 UTCEPSS rescore
  72. 2026-08-04 15:10 UTCEPSS rescore
  73. 2026-08-04 10:38 UTCEPSS rescore
  74. 2026-08-04 03:16 UTCEG score recompute
  75. 2026-08-04 03:16 UTCVendor advisory

Related CVEs(same product + same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-39817?
CVE-2026-39817 is a medium vulnerability published on May 7, 2026. 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.
When was CVE-2026-39817 disclosed?
CVE-2026-39817 was first published on May 7, 2026, with the most recent update on May 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-39817 actively exploited?
CVE-2026-39817 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (4th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-39817?
CVE-2026-39817 has a CVSS v3 base score of 5.9 (NVD).
How do I remediate CVE-2026-39817?
A fix for CVE-2026-39817 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-39817 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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