CVE-2026-4821

Rejected record published in error

Published Apr 21, 2026 · Updated Apr 21, 2026

CVE-2026-4821 no longer identifies a confirmed GitHub Enterprise Server vulnerability because GitHub rejected the record as published in error. The withdrawn record described the Management Console configuration API passing shell metacharacters from proxy fields into OS command execution. The withdrawn claim required Management Console administrator access and would have executed commands as the appliance admin OS user, but it is not a current vulnerability assertion.

CVSS severityUnavailable
Unscored
EPSS probabilityUnavailable
No score available in this record
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

CVE-2026-4821 no longer identifies a confirmed GitHub Enterprise Server vulnerability because GitHub rejected the record as published in error. The withdrawn record described the Management Console configuration API passing shell metacharacters from proxy fields into OS command execution. The withdrawn claim required Management Console administrator access and would have executed commands as the appliance admin OS user, but it is not a current vulnerability assertion.

The record

CVE
CVE-2026-4821
Published
Apr 21, 2026
Updated
Apr 21, 2026
Vendor
Twitter
Product
GitHub Enterprise Server
Classifications
Unavailable
Attack vector
Unavailable
Privileges
Unavailable

Timeline

How it unfolded

  1. Apr 21, 2026CVE publishedPublication date reported by the CVE source.
  2. Apr 21, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=3.14.0 <=3.14.25 changes=[{"at":"3.14.26","status":"unaffected"}]
  2. Affected versionversion=3.15.0 <=3.15.20 changes=[{"at":"3.15.21","status":"unaffected"}]
  3. Affected versionversion=3.16.0 <=3.16.16 changes=[{"at":"3.16.17","status":"unaffected"}]
  4. Affected versionversion=3.17.0 <=3.17.13 changes=[{"at":"3.17.14","status":"unaffected"}]
  5. Affected versionversion=3.18.0 <=3.18.7 changes=[{"at":"3.18.8","status":"unaffected"}]
  6. Affected versionversion=3.19.0 <=3.19.4 changes=[{"at":"3.19.5","status":"unaffected"}]
  7. Affected versionversion=3.20.0 <3.20.1 changes=[{"at":"3.20.1","status":"unaffected"}]

What conditions does exploitation require?

Attack vectorUnavailable in this record.
Required privilegesUnavailable in this record.

What is affected?

Twitter · GitHub Enterprise Serverversion=3.14.0 <=3.14.25 changes=[{"at":"3.14.26","status":"unaffected"}]; version=3.15.0 <=3.15.20 changes=[{"at":"3.15.21","status":"unaffected"}]; version=3.16.0 <=3.16.16 changes=[{"at":"3.16.17","status":"unaffected"}]; version=3.17.0 <=3.17.13 changes=[{"at":"3.17.14","status":"unaffected"}]; version=3.18.0 <=3.18.7 changes=[{"at":"3.18.8","status":"unaffected"}]; version=3.19.0 <=3.19.4 changes=[{"at":"3.19.5","status":"unaffected"}]; version=3.20.0 <3.20.1 changes=[{"at":"3.20.1","status":"unaffected"}]

Published CVSS scores

No CVSS assessment is available in this record.

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
VectorUnavailable
PrivilegesUnavailable
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

No sourced classifications are available.

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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