CVE-2023-39323

CRITICALNVD 8.19.8
EchelonGraph scoreMEDIUM confidence

“▲” beside the score: it is higher than NVD's CVSS score.

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2023-10-05. NVD baseline CVSS 8.1; sources differ by 1.7.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 1.9%CVSS: 8.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

Line directives ("//line") can be used to bypass the restrictions on "//go:cgo_" directives, allowing blocked linker and compiler flags to be passed during compilation. This can result in unexpected execution of arbitrary code when running "go build". The line directive requires the absolute path of the file in which the directive lives, which makes exploiting this issue significantly more complex.

CVSS v3
8.1
EG Score
9.8CRITICALmedium confidence
EG Risk
45
EG Risk 45/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation1.9% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
1.9%
EPSS %ILE
79th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
1.9% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-22). FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). All three are CISA's SSVC values (Vulnrichment). EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact total (CISA Vulnrichment). Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

October 5, 2023

Last Modified

June 12, 2025

Advisory Details (9)

Auto-updated Sep 18, 2026
Patch available.
Web page

Go: Multiple Vulnerabilities (GLSA 202311-09) — Gentoo security

https://security.gentoo.org/glsa/202311-09
Web page

GO-2023-2095 - Go Packages

https://pkg.go.dev/vuln/GO-2023-2095
Web page

[SECURITY] Fedora 39 Update: golang-1.21.3-1.fc39 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/XFOIBB4YFICHDM7IBOP7PWXW3FX4HLL2/
Web page

[SECURITY] Fedora 38 Update: golang-1.20.10-2.fc38 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/KSEGD2IWKNUO3DWY4KQGUQM5BISRWHQE/
Web page

[SECURITY] Fedora 37 Update: golang-1.20.10-3.fc37 - package-announce - Fedora mailing-lists

https://lists.fedoraproject.org/archives/list/[email protected]/message/CLB4TW7KALB3EEQWNWCN7OUIWWVWWCG2/
Web page

cmd/go: line directives allows arbitrary execution during build (CVE-2023-39323) · Issue #63211 · golang/go · GitHub

https://go.dev/issue/63211

Vendor Advisories for CVE-2023-39323(1)

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

Patch Availability(5)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntugolang-1.21-src (1.21.1-1~ubuntu20.04.2) @ focal2026-10-23ubuntu
ubuntugolang-1.17-src (1.17.13-3ubuntu1.3) @ jammy2026-10-23ubuntu
ubuntugolang-1.18-src (1.18.1-1ubuntu1~20.04.3) @ focal2026-10-23ubuntu
redhatubi8/go-toolset:1.20.10-32023-11-16redhat
redhatgo-toolset:rhel8-8090020231013032436.26eb71ac2023-11-14redhat

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

(3 across 3 ecosystems)
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
—
Go(1)
PackageVulnerable rangeFix by version rangeDependents
toolchain—
  • every version up to 1.20.9: fixed in 1.20.9
  • 1.21.0-0 up to 1.21.2: fixed in 1.21.2
—

Additional Vendor Advisories

(5)

Data Freshness Timeline

(refreshed 29× in last 7d / 65× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. 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. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

Showing the most recent 92 of 240 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. 8 repeat rows among the latest 100 are merged into the row they repeat. The 148 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-23 16:29 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  2. 2026-10-23 01:04 UTCEG score recompute
  3. 2026-10-23 01:04 UTCVendor advisory
  4. 2026-10-23 01:04 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  5. 2026-10-22 16:31 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  6. 2026-10-22 01:17 UTCEG score recompute
  7. 2026-10-22 01:17 UTCVendor advisory
  8. 2026-10-22 01:17 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  9. 2026-10-21 16:29 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  10. 2026-10-21 01:31 UTCEG score recompute
  11. 2026-10-21 01:31 UTCVendor advisory
  12. 2026-10-21 01:31 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-20 16:30 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  14. 2026-10-20 01:45 UTCEG score recompute
  15. 2026-10-20 01:45 UTCVendor advisory
  16. 2026-10-20 01:45 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-19 16:29 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  18. 2026-10-19 00:46 UTCEG score recompute
  19. 2026-10-19 00:46 UTCVendor advisory
  20. 2026-10-19 00:46 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  21. 2026-10-18 16:29 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  22. 2026-10-18 07:54 UTCEG score recompute
  23. 2026-10-18 01:00 UTCEG score recompute
  24. 2026-10-18 01:00 UTCVendor advisory
  25. 2026-10-18 00:59 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
Show 67 more
  1. 2026-10-17 16:30 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  2. 2026-10-17 01:12 UTCEG score recompute
  3. 2026-10-17 01:12 UTCVendor advisory
  4. 2026-10-17 01:12 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  5. 2026-10-16 16:36 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  6. 2026-10-16 01:19 UTCEG score recompute
  7. 2026-10-16 01:19 UTCVendor advisory
  8. 2026-10-16 01:19 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  9. 2026-10-15 16:29 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  10. 2026-10-14 20:47 UTCEG score recompute
  11. 2026-10-14 20:47 UTCVendor advisory
  12. 2026-10-14 20:47 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-14 16:30 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  14. 2026-10-13 16:41 UTCEG score recompute
  15. 2026-10-13 16:41 UTCVendor advisory
  16. 2026-10-13 16:41 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-13 16:30 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  18. 2026-10-12 16:53 UTCEG score recompute
  19. 2026-10-12 16:53 UTCVendor advisory
  20. 2026-10-12 16:53 UTCGHSA enrichmentGHSA-679v-hh23-h5jh · GitHub severity CRITICAL · GitHub CVSS 9.8
  21. 2026-10-12 16:31 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  22. 2026-10-11 21:47 UTCEG score recompute
  23. 2026-10-11 13:45 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  24. 2026-10-10 19:57 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  25. 2026-10-09 20:05 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  26. 2026-10-08 17:06 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  27. 2026-10-07 23:46 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  28. 2026-10-06 15:15 UTCEPSS rescoreEPSS 1.9% · 79th percentile
  29. 2026-10-05 17:41 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  30. 2026-10-04 23:20 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  31. 2026-10-03 14:23 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  32. 2026-10-01 19:48 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  33. 2026-09-30 16:28 UTCEG score recompute
  34. 2026-09-30 15:01 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  35. 2026-09-29 15:17 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  36. 2026-09-28 13:49 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  37. 2026-09-27 13:42 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  38. 2026-09-26 15:56 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  39. 2026-09-26 00:22 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  40. 2026-09-24 14:01 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  41. 2026-09-23 13:46 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  42. 2026-09-22 21:31 UTCOSV refresh
  43. 2026-09-20 20:14 UTCEPSS rescoreEPSS 1.8% · 77th percentile
  44. 2026-09-18 19:25 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  45. 2026-09-17 19:25 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  46. 2026-09-16 14:06 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  47. 2026-09-16 05:11 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  48. 2026-09-12 14:58 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  49. 2026-09-11 14:50 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  50. 2026-09-11 09:34 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  51. 2026-09-08 21:58 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  52. 2026-09-07 15:59 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  53. 2026-09-06 13:45 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  54. 2026-09-05 15:26 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  55. 2026-09-04 13:58 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  56. 2026-09-04 05:04 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  57. 2026-09-03 16:46 UTCOSV refresh
  58. 2026-09-02 14:09 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  59. 2026-09-01 13:51 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  60. 2026-08-30 19:15 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  61. 2026-08-30 01:20 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  62. 2026-08-28 21:39 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  63. 2026-08-27 14:23 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  64. 2026-08-26 14:43 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  65. 2026-08-25 13:46 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  66. 2026-08-23 00:17 UTCEPSS rescoreEPSS 1.8% · 76th percentile
  67. 2026-08-21 23:47 UTCEPSS rescoreEPSS 1.8% · 76th percentile

Frequently asked(5)

What is CVE-2023-39323?
CVE-2023-39323 is a critical-severity vulnerability; its CVE record was published on October 5, 2023. Line directives ("//line") can be used to bypass the restrictions on "//go:cgo_" directives, allowing blocked linker and compiler flags to be passed during compilation. This can result in unexpected execution of arbitrary code when running "go build". The line directive requires the absolute path…
When was the CVE record for CVE-2023-39323 published?
The CVE record for CVE-2023-39323 was published on October 5, 2023. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of June 12, 2025; the record at its source may have been updated since.
Is CVE-2023-39323 actively exploited?
CVE-2023-39323 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.9% probability of exploitation in the next 30 days (79th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2023-39323?
CVE-2023-39323 has a CVSS v3 base score of 8.1 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.8 (CRITICAL).
How do I remediate CVE-2023-39323?
A fix for CVE-2023-39323 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2023-39323 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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