CVE-2021-35440 json
Smashing Cross-site Scripting vulnerability
published 2021-07-06 5 y ago modified 2026-06-17 4 mo ago also GHSA-254j-mmc5-qhpx , EUVD-2022-1905
- cvss
- 6.1
- version 3.1, NVD
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 62%
- public exploits
- 0
- none known
Summary
Smashing 1.3.4 is vulnerable to Cross Site Scripting (XSS). A URL for a widget can be crafted and used to execute JavaScript on the victim's computer. The JavaScript code can then steal data available in the session/cookies depending on the user environment (e.g. if re-using internal URL's for deploying, or cookies that are very permissive) private information may be retrieved by the attacker.
Patch / fix
- rubygems smashing 1.3.5
- github.com/Smashing/smashing#186 commit
- github.com/Smashing/smashing#186 pull request
Exploit prediction
1.00% chance of exploitation in the next 30 days, higher than 62% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 2.0 | 4.3 | AV:N/AC:M/Au:N/C:N/I:P/A:N |
| GitHub | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| rubygems | smashing | <1.3.5 |
1.3.5 |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/Smashing/smashing/pull/186
web, patch, third-party-advisory
-
github.com
/Smashing/smashing/pull/186#issuecomment-871727614
patch, third-party-advisory
-
github.com
/Smashing/smashing/pull/186/commits/f4648137ae77aa2a9ccd14b2e6eeaed2cfb32da3
web
-
github.com
/Smashing/smashing/blob/ad7325f159f89854ca4e7d94e7be9bee507b6d46/CHANGELOG.md
web, release-notes, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-35440
advisory
-
github.com
/Smashing/smashing
package
-
github.com
/rubysec/ruby-advisory-db/blob/master/gems/smashing/CVE-2021-35440.yml
web
Sources
- CVE List CVE-2021-35440
- GitHub Advisory GHSA-254j-mmc5-qhpx
- NVD CVE-2021-35440
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