CVE-2026-12391

MEDIUMPre-NVD 5.05.0—
EchelonGraph scoreHIGH confidence

Score 5.0 from GitHub Security Advisory published 2026-07-16. a secondary CVSS source baseline 5.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
5.0EG
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 5.0Exploit: None knownExposed: 0

A fix is available — apply it.

An insecure symlink following vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools) within the pro collect-logs command framework. The utility creates or utilizes predictable temporary file paths or user-accessible log directories when gathering diagnostic information without verifying the file type or ownership. An unprivileged local attacker can exploit this behavior by creating a symbolic link (symlink) at a predictable destination path pointing to an arbitrary, root-readable file (such as /etc/shadow or private files within /root). When a root administrator or operator subsequently executes the pro collect-logs command, the tool follows the user-controlled symlink, reads the target file, and compresses its contents into the resulting diagnostic support archive. Because the output archive remains readable by the unprivileged user, the attacker can extract and read the sensitive root-owned files, leading to a complete information disclosure of system secrets.

CVSS v3
5.0
EG Score
5.0(high)
EG Risk
23(Track)
EG Risk 23/100SSVC: Track

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
Severity50% × 45%
Exploitation0% × 40%
Automatability0% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
5%
KEV
Not listed

Published

July 16, 2026

Last Modified

July 16, 2026

References (1)

Vendor Advisories for CVE-2026-12391(1)

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

Patch Availability(1)

Vendor / EcosystemFixed in / PatchReleasedSource
ubuntuubuntu-pro-client-l10n (37.1ubuntu0~16.04.1) @ xenial2026-07-27ubuntu

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.

Weakness Classification(1)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 17× in last 7d / 26× 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.

  1. 2026-07-28 15:36 UTCEPSS rescore
  2. 2026-07-28 11:25 UTCEG score recompute
  3. 2026-07-28 11:25 UTCGHSA enrichment
  4. 2026-07-27 14:13 UTCEPSS rescore
  5. 2026-07-27 11:09 UTCEG score recompute
  6. 2026-07-27 11:09 UTCVendor advisory
  7. 2026-07-27 11:09 UTCGHSA enrichment
  8. 2026-07-26 14:54 UTCEPSS rescore
  9. 2026-07-26 14:54 UTCEPSS rescore
  10. 2026-07-26 11:26 UTCEG score recompute
  11. 2026-07-26 11:26 UTCVendor advisory
  12. 2026-07-26 11:26 UTCGHSA enrichment
  13. 2026-07-25 14:17 UTCEPSS rescore
  14. 2026-07-24 14:17 UTCEPSS rescore
  15. 2026-07-23 14:18 UTCEPSS rescore
  16. 2026-07-23 03:05 UTCEG score recompute
  17. 2026-07-22 14:08 UTCEPSS rescore
  18. 2026-07-21 15:24 UTCEPSS rescore
  19. 2026-07-20 17:08 UTCEPSS rescore
  20. 2026-07-19 14:30 UTCEPSS rescore
  21. 2026-07-19 02:28 UTCEPSS rescore
  22. 2026-07-18 10:04 UTCEPSS rescore
  23. 2026-07-17 07:03 UTCEG score recompute
  24. 2026-07-17 07:03 UTCGHSA enrichment
  25. 2026-07-16 12:49 UTCEG score recompute
Show 1 more
  1. 2026-07-16 12:48 UTCMITRE cvelistV5first tracked

Related CVEs(same vendor + same CWE)

Frequently asked(5)

What is CVE-2026-12391?
CVE-2026-12391 is a medium vulnerability published on July 16, 2026. An insecure symlink following vulnerability exists in Canonical ubuntu-pro-client (formerly ubuntu-advantage-tools) within the pro collect-logs command framework. The utility creates or utilizes predictable temporary file paths or user-accessible log directories when gathering diagnostic…
When was CVE-2026-12391 disclosed?
CVE-2026-12391 was first published in the National Vulnerability Database on July 16, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-12391 actively exploited?
CVE-2026-12391 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 94.5% of all scored CVEs.
What is the CVSS score of CVE-2026-12391?
CVE-2026-12391 has a CVSS v3 base score of 5.0 (NVD).
How do I remediate CVE-2026-12391?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-12391, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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