VulnerabilityPublished 8 Jun 2026

CVE-2026-11511: Bolt CMS · Basic Cross Site Scripting

Affects Bolt CMSSource CVE Database V5

Public exploit available · CVSS 5.1 Medium · end of life, no fix coming : replace or isolate Bolt CMS; no fix will be released.

Data as of 30 Oct 2026, 11:52 UTC

CVSS 4.0 base score

5.1Medium

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

EPSS: 0.1% chance of exploitation in 30 days – higher than 8% of CVEsExploit Prediction Scoring System: the likelihood attackers will use this flaw soon.
Patch: None coming – the product is end of life

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N/E:P

Base metrics

Attack Vector: Network
Attack Complexity: Low
Attack Requirements: None
Privileges Required: Low
User Interaction: Passive
Vulnerable system confidentiality: None
Vulnerable system integrity: Low
Vulnerable system availability: None
Subsequent system confidentiality: None
Subsequent system integrity: None
Subsequent system availability: None

Threat metrics

Exploit Maturity: POC

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

Attack Vector: Network: The vulnerable system is bound to the network stack and the set of possible attackers extends beyond the other options listed below, 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: The attacker must take no measurable action to exploit the vulnerability. The attack requires no target-specific circumvention to exploit the vulnerability. An attacker can expect repeatable success against the vulnerable system.
Attack Requirements: None: The successful attack does not depend on the deployment and execution conditions of the vulnerable system. The attacker can expect to be able to reach the vulnerability and execute the exploit under all or most instances of the vulnerability.
Privileges Required: Low: The attacker requires privileges that provide basic capabilities that are typically limited to settings and resources owned by a single low-privileged user. Alternatively, an attacker with Low privileges has the ability to access only non-sensitive resources.
User Interaction: Passive: Successful exploitation of this vulnerability requires limited interaction by the targeted user with the vulnerable system and the attacker’s payload. These interactions would be considered involuntary and do not require that the user actively subvert protections built into the vulnerable system.
Vulnerable system confidentiality: None: There is no loss of confidentiality within the Vulnerable System.
Vulnerable system 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 to the Vulnerable System.
Vulnerable system availability: None: There is no impact to availability within the Vulnerable System.
Subsequent system confidentiality: None: There is no loss of confidentiality within the Subsequent System or all confidentiality impact is constrained to the Vulnerable System.
Subsequent system integrity: None: There is no loss of integrity within the Subsequent System or all integrity impact is constrained to the Vulnerable System.
Subsequent system availability: None: There is no impact to availability within the Subsequent System or all availability impact is constrained to the Vulnerable System.
Exploit Maturity: POC: Based on threat intelligence sources each of the following must apply: · Proof-of-concept is publicly available · No knowledge of reported attempts to exploit this vulnerability · No knowledge of publicly available solutions used to simplify attempts to exploit the vulnerability

Definitions: FIRST CVSS v4.0 specification.

Exploitation evidence

Disclosed: evidence found.
CVE published 8 Jun 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: evidence found.
CVSS exploit maturity: proof of concept public
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), CVSS vector, 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

No fix will be released: Bolt CMS is end of life. Replace it, or isolate it from untrusted networks until you can.

Affected software

Product	Affected	Fixed in
BoltCMS	Affected 3.7.0 – 3.7.5 6 affected builds	Fixed in–
Packagistbolt/cms`pkg:composer/bolt/cms`Other threats	Affected 3.7.0 – 3.7.5 6 affected builds	Fixed in–

CPE configurations (1)

cpe:2.3:a:bolt:cms:*:*:*:*:*:*:*:*

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

AI-suggested

Users are advised to upgrade to a supported version of Bolt CMS if available or migrate to alternative solutions. Until then, mitigating exposure by restricting access or sanitizing inputs at the application or web server level may reduce risk.

Description

A weakness has been identified in Bolt CMS up to 3.7.5. This vulnerability affects unknown code of the file src/Storage/Field/Type/TextType.php of the component HTML Attribute Handler. Executing a manipulation of the argument style can lead to HTML injection. It is possible to launch the attack remotely. The exploit has been made available to the public and could be used for attacks. The GitHub repository was archived by the owner and is now read-only. This vulnerability only affects products that are no longer supported by the maintainer.

Impact

Successful exploitation of this vulnerability can allow an attacker to inject arbitrary HTML, potentially leading to cross-site scripting attacks. This could enable attackers to execute scripts in the context of users visiting the affected Bolt CMS site, possibly leading to session hijacking or other client-side impacts. However, the impact is limited by the need for user interaction and the low privileges required for the attack. Since the affected versions are unsupported, users remain exposed unless they upgrade or migrate.

Summary

Bolt CMS versions 3.7.0 through 3.7.5 contain a vulnerability in the HTML Attribute Handler component where manipulation of the 'style' argument can lead to HTML injection. This is classified as a basic cross-site scripting vulnerability. The flaw exists in the file src/Storage/Field/Type/TextType.php. The vulnerability can be exploited remotely without requiring elevated privileges, though user interaction is needed. The affected Bolt CMS versions are no longer maintained, and the source repository is archived, indicating no forthcoming official fixes. The CVSS 4.0 vector indicates network attack vector, low attack complexity, low privileges required, and user interaction needed, with partial impact on integrity and availability but no impact on confidentiality or scope.

References

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