VulnerabilityPublished 13 Nov 2026

CVE-2026-126349: Uffizzi · Addressable display_uri can show misleading hosts containing bidi and invisible characters

Affects uffizziSource GCVE Database

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Authoritative record:CVE-2026-126349· Low 3.1

Not known to be exploited · CVSS 3.1 Low · fixed in 2.9.1 : update uffizzi when convenient.

Data as of 13 Nov 2026, 21:05 UTC

CVSS 3.1 base score

3.1Low

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

Thin evidence

One scorer or none

CVSS scores by source
CNA (GitHub_M)	CVSS 3.1	3.1

Patch: Available – fixed in 2.9.1

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

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

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: High: A successful attack depends on conditions beyond the attacker's control. That is, a successful attack cannot be accomplished at will, but requires the attacker to invest in some measurable amount of effort in preparation or execution against the vulnerable component before a successful attack can be expected. For example, a successful attack may require an attacker to: gather knowledge about the environment in which the vulnerable target/component exists; prepare the target environment to improve exploit reliability; or inject themselves into the logical network path between the target and the resource requested by the victim in order to read and/or modify network communications (e.g., a man in the middle attack).
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: None: There is no loss of confidentiality within the impacted component.
Integrity: Low: Modification of data is possible, but the attacker does not have control over the consequence of a modification, or the amount of modification is limited. The data modification does not have a direct, serious impact on the impacted component.
Availability: None: There is no impact to availability within the impacted component.

Definitions: FIRST CVSS v3.1 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 12 Nov 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 13 Nov 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

Affected software

Product	Affected	Fixed in
Homebrewuffizzi`pkg:brew/uffizzi`Other threats	Affected >=2.3.4	Fixed in–

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AI-suggested

A fix is available in Addressable version 2.9.1 for both the pure-Ruby and native IDNA implementations. Users should upgrade to version 2.9.1 or later. As a workaround, installing libidn and the idn-ruby gem forces use of the native IDNA implementation, reducing the set of problematic characters. Additionally, applications should detect bidirectional and invisible characters in displayed hosts and fallback to using normalized_host instead of display_uri when such characters are present.

Description

Addressable library versions 2.0.0 and later have a vulnerability in the display_uri method where Unicode bidirectional and invisible characters in Punycode-encoded hostnames can cause misleading visual representations. This can make malicious domains appear as trusted ones in user interfaces that display these URIs. The issue is fixed in version 2.9.1.

Impact

This vulnerability allows attackers to craft domain names that visually impersonate trusted hosts by exploiting bidirectional and invisible Unicode characters in Punycode labels. This can lead to user deception in interfaces that display the URI using display_uri, such as link previews, chat clients, email clients, and admin panels. There is no impact on URI parsing or network connections, so the risk is limited to visual spoofing and user interface deception. The CVSS score is low (3.1) reflecting the requirement for user interaction and the limited scope of impact.

Summary

The vulnerability arises from the Addressable::IDNA.to_unicode method decoding Punycode labels containing bidirectional control characters (e.g., U+202E RIGHT-TO-LEFT OVERRIDE) and invisible format characters, which affect the visual rendering of hostnames in display_uri. While parsing and connection logic remain unaffected, the displayed hostname can visually reorder characters or mimic other trusted domains, potentially misleading users. The pure-Ruby IDNA implementation (Addressable >= 2.0.0) decodes all such characters, including those disallowed by IDNA's nameprep profile. The native IDNA implementation (Addressable >= 2.5.2) rejects most but not all problematic characters, especially those added after Unicode 3.2. The vulnerability is resolved in Addressable 2.9.1 by returning such labels unchanged.

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What to do

Affected software

Description

AI analysisMachine-generated, updated 13 Nov 2026, 21:05 UTC

Technical details

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