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NVD / CVE Program· CNA GitHub_M

CVE-2026-25742: Zulip: Anonymous File Access After Disabling Spectator Access

Noroxi assessment

Priority: Monitor (action score 21/100)

  • 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: 0.32% (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.
  • According to CISA the attack is automatable: targets can be found by mass scanning.
  • Fixed version: zulip zulip 11.6.

Low priority for now. Upgrade to zulip zulip 11.6 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

Zulip is an open-source team collaboration tool. Prior to version 11.6, Zulip is an open-source team collaboration tool. From version 1.4.0 to before version 11.6, even after spectator access (enable_spectator_access / WEB_PUBLIC_STREAMS_ENABLED) is disabled, attachments originating from web-public streams can still be retrieved anonymously. As a result, file contents remain accessible even after public access is intended to be disabled. Similarly, even after spectator access is disabled, the /users/me/<stream_id>/topics endpoint remains reachable anonymously, allowing retrieval of topic history for web-public streams. This issue has been patched in version 11.6. This issue has been patched in version 11.6.

MediumCVSS 5.3 · v3.1—No exploit Fix available
Published
Apr 3, 2026
Updated
Jul 24, 2026
EPSS
0.3% · 25th percentile

Report tools

JSON

Action score

21

Monitor

Low priority for now.

CVSS
21 / 40 · 5.3 / 10
CISA KEV
0 / 30 · Not listed
EPSS
0 / 30 · 0.3%

CISA SSVC decision

Exploitation
proof of concept
Automatable
yes
Technical impact
partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD
—
CNA · GitHub_M
5.3
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.

Follow CVE-2026-25742

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.

VendorProduct
zulipzulip

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

  • zulip zulip1.4.0 and later · before 11.6

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.

  • zulip zulip

    • < 11.6affected

Same product

zulip: all records

Other highest-scoring records for the same primary product.

  • CVE-2021-43799RabbitMQ exposes ports with weak default secrets in Zulip Server
    41Plan
  • CVE-2026-102893Zulip: OpenID Connect authentication ignores the email_verified claim
    36Monitor
  • CVE-2022-31168Zulip Server insufficient authorization for changing bot roles
    35Monitor

Published before and after this one in the same product

  • ← EarlierCVE-2025-47930May 15, 2025 · Zulip Server has access control bypass for restrictions on creation of specific channel types
    21Monitor
  • ← EarlierCVE-2026-25741Feb 26, 2026 · Zulip Vulnerable to Modification of Payment Method (Stripe Default Card) by Non-Billing Users
    28Monitor
  • Later →CVE-2026-26058Apr 3, 2026 · Zulip: Path Traversal in Import
    24Monitor

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
zulip zulip11.6 · 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.

No dated events beyond publication.

No history yet (it accumulates with the daily EPSS job).

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.

  • CVE-2026-100404194 days apartZulip: Guests can read new messages in non-subscribed public channels
    26Monitor
  • CVE-2026-115474215 days apartZulip: Saving a draft DM to a user bypasses can_access_all_users_group permission
    26Monitor
  • CVE-2026-115574215 days apartZulip: Custom profile fields can be read by logged-out visitors in organization with web-public channels
    21Monitor

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

Weakness class (CWE)

CWE-862 · Missing Authorization

CVSS vector

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

nvd-secondary

Attack context

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

Change log

  1. Fix✗ → ✓

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