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NVD / CVE Program· CNA GitHub_M

CVE-2026-85708: Chartbrew: Private chart data disclosure via forgeable CB_SECRET share tokens

Noroxi assessment

Priority: Monitor (action score 30/100)

  • The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
  • Probability of exploitation in the next 30 days: 0.19% (FIRST EPSS).
  • Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
  • Fixed version: chartbrew chartbrew 5.2.3.

Low priority for now. Upgrade to chartbrew chartbrew 5.2.3 or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Chartbrew is an open-source web application that can connect directly to databases and APIs and use the data to create charts. Prior to 5.2.3, Chart share and embed tokens were signed with CB_SECRET, including known or shipped-default values in stock source and repository Docker Compose installs. The vulnerable surface is chart share-token verification and filter-access routes for private charts. An attacker who knows the deployment's CB_SECRET targets a private chart that has been shared at least once so a share-policy row exists, then forges a Chart-subject token for that chart id. The known signing key permits valid Chart tokens, and the filter-access path accepts sequential integer ids without requiring a legitimate share link; token expiry and revocation are ineffective once the secret is known. The condition requires a known or default secret and an existing share-policy row. A bare container where CB_SECRET is undefined is outside this path, and a unique secret excludes it only while the value remains unknown and unpredictable. An unauthenticated attacker can enumerate integer ids and read arbitrary private chart data, including chartData, without possessing a legitimate share link. This issue is fixed in version 5.2.3.

HighCVSS 7.5 · v3.1—No exploit Fix available
Published
Nov 6, 2026
Updated
Nov 6, 2026
EPSS
0.1% · 9th percentile

Report tools

JSON

Action score

30

Monitor

Low priority for now.

CVSS
30 / 40 · 7.5 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.1%

CNA vs NVD score

NVD
—
CNA · GitHub_M
7.5
NVD has not scored this yet; the score shown is the CNA’s.

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

  • Not in KEV: no record of exploitation in the wild
  • No public exploit code on record
  • A fix has been released

If any of these changes, we'll tell you in the daily email digest.

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When you'll hear from us

  • when it enters CISA KEV
  • when exploit code appears or is weaponized
  • when the record is updated (including a fixed version)
  • when EPSS rises 20 points in a week

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

—

Versions reported by the vendor

Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.

  • chartbrew chartbrew

    • < 5.2.3affected

Same product

chartbrew: all records

Other highest-scoring records for the same primary product.

  • CVE-2026-85295Chartbrew: Full account takeover via JWTs accepted under default CB_SECRET
    39Monitor
  • CVE-2026-54349Chartbrew SQL injection in dashboard filter substitution
    39Monitor
  • CVE-2026-86005Chartbrew: Unauthenticated BullMQ Admin Dashboard Exposure in Chartbrew
    37Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2026-65980Sep 21, 2026 · Chartbrew: SQL Injection via Missing Backslash Escaping in ClickHouse Variable Substitution
    31Monitor
  • ← EarlierCVE-2026-54589Nov 6, 2026 · Chartbrew: SSRF guard bypass via IPv6 NAT64/DNS64 addresses in API Data Connection outbound policy (validateOutboundUrl)
    28Monitor
  • Later →CVE-2026-85712Nov 6, 2026 · Chartbrew: Cross-tenant project takeover via body.team_id in /project routes
    35Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / packageFixed versionSource
chartbrew chartbrew5.2.3 · descriptionVendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

  1. Published
  2. Fix recordedsame day
  3. TodayNov 9, 2026+3 d
EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

  • Anyone who can reach it over the internet can trigger it.
  • No account or password is required.
  • No user action is required.
  • No special conditions are required; it is repeatable.

If successful

Confidentiality
high · data can be read
Integrity
none
Availability
none
Attack vector
Network
Attack complexity
Low
Privileges required
None
User interaction
None
Scope
Unchanged
Confidentiality impact
High
Integrity impact
None
Availability impact
None

Weakness class (CWE)

CWE-347 · Improper Verification of Cryptographic Signature

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

nvd-secondary

Root cause

The verifier takes the algorithm to verify with from the token’s own header. Untrusted data ends up deciding its own verification rule.

The bug in code

The whole CWE-347 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

ts
const claims = jwt.verify(token, publicKey);

Fixed

ts
const claims = jwt.verify(token, publicKey, {  algorithms: ["RS256"],  issuer: "https://id.example.com",  audience: "portal",});

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

ATT&CK techniques

—

Change log

  1. Fix✗ → ✓
  2. Exploit maturity— → none

For records you follow, these changes also arrive as notifications. →

References

Show all references (2 more)

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records