VulnerabilityPublished 2 Mar 2026

CVE-2026-28403: textream · Origin Validation Error

Affects textreamSource CVE Database V5

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Not known to be exploited · CVSS 7.6 High : upgrade to 1.5.1 soon.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 3.1 base score

7.6High

How severe the flaw is on the 0–10 CVSS scale.

EPSS: 0.1% chance of exploitation in 30 days – higher than 6% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: Available – fixed in 1.5.1

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

Attack Vector: Network
Attack Complexity: Low
Privileges Required: None
User Interaction: Required
Scope: Unchanged
Confidentiality: Low
Integrity: High
Availability: Low

Bold values are the worst case: easiest to exploit or largest impact.

Attack Vector: Network: The vulnerable component is bound to the network stack and the set of possible attackers extends beyond the other options listed, up to and including the entire Internet. Such a vulnerability is often termed 'remotely exploitable' and can be thought of as an attack being exploitable at the protocol level one or more network hops away (e.g., across one or more routers).
Attack Complexity: Low: Specialized access conditions or extenuating circumstances do not exist. An attacker can expect repeatable success against the vulnerable component.
Privileges Required: None: The attacker is unauthorized prior to attack, and therefore does not require any access to settings or files to carry out an attack.
User Interaction: Required: Successful exploitation of this vulnerability requires a user to take some action before the vulnerability can be exploited.
Scope: Unchanged: An exploited vulnerability can only affect resources managed by the same security authority. In this case, the vulnerable component and the impacted component are either the same, or both are managed by the same security authority.
Confidentiality: Low: There is some loss of confidentiality. Access to some restricted information is obtained, but the attacker does not have control over what information is obtained, or the amount or kind of loss is limited. The information disclosure does not cause a direct, serious loss to the impacted component.
Integrity: High: There is a total loss of integrity, or a complete loss of protection. For example, the attacker is able to modify any/all files protected by the impacted component. Alternatively, only some files can be modified, but malicious modification would present a direct, serious consequence to the impacted component.
Availability: Low: Performance is reduced or there are interruptions in resource availability. Even if repeated exploitation of the vulnerability is possible, the attacker does not have the ability to completely deny service to legitimate users. The resources in the impacted component are either partially available all of the time, or fully available only some of the time, but overall there is no direct, serious consequence to the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 2 Mar 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors

A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 30 Oct 2026.

Disclosed: The CVE record is public on cve.org. Its publication is t = 0.
Detectable: A public nuclei template can find exposed instances, for defenders and attackers alike.
Weaponized: A Metasploit exploit module or Exploit-DB entry exists (Metasploit scanner modules do not count), or CISA SSVC or the CVSS exploit maturity reports a public proof of concept.
Exploited in the wild: CISA KEV lists it, CISA SSVC rates exploitation active, or a source reports attacks.
Observed by OffSeq Mirage: OffSeq Mirage honeypot sensors recorded attack traffic for this CVE, or found exposed hosts without attack traffic.

Moments are spaced evenly, not to scale; a dashed line marks a gap of six months or more. Deltas count from t = 0. Sources that give only a date (CISA KEV, Exploit-DB, or a time of exactly 00:00Z) read “same day” rather than hours. Metasploit modules carry the flaw’s disclosure date, not their release date, and nuclei templates carry no date, so both appear above but not on the timeline.

What to do

Upgrade textream and f/textream to 1.5.1.

Affected software

Product	Affected	Fixed in
textream	Affected <1.5.1	Fixed in 1.5.1
GitHubf/textream`pkg:github/f/textream`Other threats	Affected <1.5.1	Fixed in 1.5.1

Check your own hosts for these packages with threat-finder (opens in a new tab), our free open-source scanner.

AI-suggested

Immediate upgrade of Textream to version 1.5.1 or later is the primary mitigation, as this version includes proper Origin header validation. Until upgrade, organizations should restrict access to untrusted web content on systems running vulnerable versions to reduce the risk of malicious web pages establishing WebSocket connections. Employ browser security controls such as disabling or limiting WebSocket connections from untrusted origins, using browser extensions or policies that block suspicious scripts, and educating users about the risks of visiting untrusted websites. Network-level controls can also be implemented to restrict loopback WebSocket connections if feasible. Monitoring local WebSocket server activity for unusual connections or commands may help detect exploitation attempts. Finally, organizations should consider alternative teleprompter solutions if immediate patching is not possible.

Description

Textream is a free macOS teleprompter app. Prior to version 1.5.1, the `DirectorServer` WebSocket server (`ws://127.0.0.1:<httpPort+1>`) accepts connections from any origin without validating the HTTP `Origin` header during the WebSocket handshake. A malicious web page visited in the same browser session can silently connect to the local WebSocket server and send arbitrary `DirectorCommand` payloads, allowing full remote control of the teleprompter content. Version 1.5.1 fixes the issue.

Impact

The vulnerability allows attackers to remotely control the teleprompter content on affected macOS systems running Textream versions prior to 1.5.1. This can lead to misinformation during live presentations or broadcasts, undermining the integrity of the content displayed. Confidentiality is moderately impacted as an attacker could potentially infer or manipulate displayed text. Availability impact is low but present, as the teleprompter could be disrupted or rendered unusable. Organizations relying on Textream for professional or public-facing presentations risk reputational damage, misinformation dissemination, and operational disruption. Since exploitation requires user interaction (visiting a malicious web page), targeted phishing or watering hole attacks could be used to compromise specific high-value targets. The vulnerability is particularly concerning in environments where teleprompter content integrity is critical, such as media companies, government communications, and corporate presentations.

CWE-346Origin Validation Error (opens in a new tab)
Class weaknessOWASP Top 10 A07:2025: Authentication Failures (opens in a new tab)
The product does not properly verify that the source of data or communication is valid.
OWASP Cheat Sheets
OWASP Authentication (opens in a new tab)
OWASP ASVS 4.0.3
V14.5.2 (opens in a new tab)
V14.5.3 (opens in a new tab)
V1.4.4 (opens in a new tab)
Attack patterns
JSON Hijacking (aka JavaScript Hijacking) (opens in a new tab)
Cache Poisoning (opens in a new tab)
DNS Cache Poisoning (opens in a new tab)
Exploit Script-Based APIs (opens in a new tab)
Application API Message Manipulation via Man-in-the-Middle (opens in a new tab)
From MITRE CWE, MITRE CAPEC and OWASP (Top 10, OpenCRE).

References

Community reviews

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Exploitation evidence

What to do

Affected software

Description

AI analysisMachine-generated, updated 9 Mar 2026, 17:20 UTC

WeaknessesCWE-346

Technical details

References

Community reviews

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