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TI-2021-08524 Aliases CVE-2021-26918GHSA-ghmj-xphc-2mq4

The ProBot bot through 2021-02-08 for Discord might allow attackers to interfere with the…

Priority HIGH 82CWE-434Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Code execution
Confidentiality · integrity · availability
High · High · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-434.

Summary

The ProBot bot through 2021-02-08 for Discord might allow attackers to interfere with the intended purpose of the "Send an image when a user joins the server" feature (or possibly have unspecified other impact) because the uploader web service allows double extensions (such as .html.jpg) with the text/html content type. NOTE: there may not be cases in which an uploader web service is customer controlled; however, the nature of the issue has substantial interaction with customer controlled configuration. NOTE: the vendor states "This is just an uploader (like any other one) which uploads files to cloud storage and accepts various file types. There is no kind of vulnerability and it won't compromise either the client side or the server side.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.02617 85th percentileScored 2026-11-07
Public exploit Yes 2 exploit referencesTagged by NVD
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
Poc
Automatable
Yes
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:probot:bot:*:*:*:*:*:discord:*:*up to 2021-02-08VulnerableProbot
  • cpe:2.3:a:probot:bot:*:*:*:*:*:discord:*:* Versions up to 2021-02-08 Vulnerable ·Probot

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2021-26918
  2. 2026-10-03 Alias added: GHSA-ghmj-xphc-2mq4

References

Exploit 2

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences