CVE-2026-93856

MEDIUMPre-NVD 4.34.3
EchelonGraph scoreHIGH confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 4.3 from GitHub Security Advisory (severity: MODERATE) published 2026-10-21. A secondary CVSS source baseline 4.3; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source
Elevated

Also known asEUVD-2026-107047 (ENISA EUVD) · GHSA-rgvg-xc9j-2jxv (GitHub Security Advisories)Source: ENISA EUVD

4.3EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 4.3Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

In OpenStack Cinder through 29.0.0, cross-project information disclosure can occur in the Messages API. A non-admin user with the project-scoped 'member' or 'reader' role making the Block Storage API v3.3 "List messages" call finds the non-expired user messages for other projects included in the response, resulting in the leakage of UUIDs of resources owned by other projects, in addition to the user message about the other projects' resources (which, by design, are sanitized generic messages). All Cinder deployments are affected.

CVSS v3
4.3
EG Score
4.3MEDIUMhigh confidence
EG Risk
35
EG Risk 35/100

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)
Severity43% × 45%
Impact severity (EG Severity): CVSS 4.3 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
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 public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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
0.4%
EPSS %ILE
31st
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 (4.3): severity, escalated by confirmed exploitation. This CVE's 4.3 is its impact severity (EG Severity), not escalated.

EG Severity
4.3 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-07). 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: 60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: 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 public PoC (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (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)60 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA Vulnrichment) · Technical impact partial (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 21, 2026

Last Modified

October 22, 2026

Advisory Details (4)

Auto-updated Nov 7, 2026
Patch available.
Web page

Bug #2160671 “[OSSA-2026-045] Cross-project information disclosu...” : Bugs : Cinder

https://bugs.launchpad.net/cinder/+bug/2160671
Web page

oss-security - [OSSA-2026-045] Cinder: Cross-project information disclosure in Cinder Messages API (CVE-2026-93856)

http://www.openwall.com/lists/oss-security/2026/10/20/17
Web page

oss-security - [OSSA-2026-045] Cinder: Cross-project information disclosure in Cinder Messages API (CVE-2026-93856)

https://www.openwall.com/lists/oss-security/2026/10/20/17
Web page

OSSA-2026-045: Cross-project information disclosure in Cinder Messages API — OpenStack Security Advisories 0.0.1.dev414 documentation

https://security.openstack.org/ossa/OSSA-2026-045.html

Vendor Advisories for CVE-2026-93856(1)

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

Affected Packages

(3 across 3 ecosystems)
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
cinder2:21.1.0-3 ... 2:29.0.0~rc1-2 (58 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
cinder2:26.0.0-2 ... 2:29.0.0~rc1-2 (20 versions)
  • every version on: no fix on record
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
cinder2:26.0.0-2 ... 2:29.0.0~rc1-2 (19 versions)
  • every version up to 2:29.0.0-3: fixed in 2:29.0.0-3
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 8× in last 7d / 30× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

  1. 2026-11-12 16:35 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  2. 2026-11-11 16:41 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  3. 2026-11-10 16:46 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  4. 2026-11-09 16:36 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  5. 2026-11-08 16:41 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  6. 2026-11-07 19:07 UTCGHSA enrichmentGHSA-rgvg-xc9j-2jxv · GitHub severity MODERATE · GitHub CVSS 4.3
  7. 2026-11-07 19:07 UTCEchelonGraph re-scored
  8. 2026-11-07 16:40 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  9. 2026-11-06 16:40 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  10. 2026-11-05 16:39 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  11. 2026-11-04 16:37 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  12. 2026-11-03 16:49 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  13. 2026-11-02 16:46 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  14. 2026-11-01 16:36 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  15. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  16. 2026-10-30 16:35 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  17. 2026-10-30 03:25 UTCOSV refresh
  18. 2026-10-29 16:34 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  19. 2026-10-28 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  20. 2026-10-27 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  21. 2026-10-26 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  22. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  23. 2026-10-25 13:49 UTCEchelonGraph re-scored
  24. 2026-10-24 16:34 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  25. 2026-10-23 16:33 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
Show 13 more
  1. 2026-10-22 17:31 UTCEchelonGraph re-scored
  2. 2026-10-22 17:31 UTCGHSA enrichmentGHSA-rgvg-xc9j-2jxv · GitHub CVSS 4.3
  3. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  4. 2026-10-21 19:26 UTCEchelonGraph re-scored
  5. 2026-10-21 19:25 UTCGHSA enrichmentGHSA-rgvg-xc9j-2jxv · GitHub CVSS 4.3
  6. 2026-10-21 19:08 UTCEchelonGraph re-scored
  7. 2026-10-21 19:08 UTCGHSA enrichmentGHSA-rgvg-xc9j-2jxv · GitHub CVSS 4.3
  8. 2026-10-21 16:34 UTCEPSS rescoreEPSS 0.3% · 23rd percentile
  9. 2026-10-21 07:26 UTCEchelonGraph re-scored
  10. 2026-10-21 07:26 UTCGHSA enrichmentGHSA-rgvg-xc9j-2jxv · GitHub CVSS 4.3
  11. 2026-10-21 06:26 UTCEchelonGraph re-scored
  12. 2026-10-21 05:48 UTCEchelonGraph re-scoredFirst assessed: 4.3 MEDIUM
  13. 2026-10-21 05:46 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-93856?
CVE-2026-93856 is a medium-severity vulnerability; its CVE record was published on October 21, 2026. In OpenStack Cinder through 29.0.0, cross-project information disclosure can occur in the Messages API. A non-admin user with the project-scoped 'member' or 'reader' role making the Block Storage API v3.3 "List messages" call finds the non-expired user messages for other projects included in the…
When was the CVE record for CVE-2026-93856 published?
The CVE record for CVE-2026-93856 was published on October 21, 2026. 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 October 22, 2026; the record at its source may have been updated since.
Is CVE-2026-93856 actively exploited?
CVE-2026-93856 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (31st percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-93856?
CVE-2026-93856 has a CVSS base score of 4.3 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-93856?
A fix for CVE-2026-93856 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-93856 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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