CVE-2021-46871 json
phoenix_html allows Cross-site Scripting in HEEx class attributes
published 2022-04-12 4 y ago modified 2026-09-10 1 mo ago also GHSA-5g2h-9x5v-5h3x , GHSA-j3gg-r6gp-95q2 , EUVD-2023-0339
- cvss
- 6.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.4%
- EPSS 0.4% chance of exploitation in 30 days, percentile 37%
- public exploits
- 0
- none known
Summary
tag.ex in Phoenix Phoenix.HTML (aka phoenix_html) before 3.0.4 allows XSS in HEEx class attributes.
Patch / fix
- npm phoenix_html 3.0.4
- hex phoenix_html 3.0.4
- phoenixframework phoenix_html 3.0.4
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 19 mo ago
Exploit prediction
0.43% chance of exploitation in the next 30 days, higher than 37% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CISA ADP | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| NVD | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N |
| CNA | 3.1 | 6.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/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 |
|---|---|---|---|
| npm | phoenix_html | <3.0.4 |
3.0.4 |
| hex | phoenix_html | <3.0.4 |
3.0.4 |
Classification
- Weakness
-
- CWE-79 Improper Neutralization of Input During Web Page Generation
References
-
github.com
/phoenixframework/phoenix_html/commit/62a0139fb716bcdce697f6221244bd81d321d620
web, patch, third-party-advisory
-
github.com
/advisories/GHSA-j3gg-r6gp-95q2
advisory, patch, third-party-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2021-46871
advisory
-
github.com
/phoenixframework/phoenix_html
web, package
Sources
- CVE List CVE-2021-46871
- GitHub Advisory GHSA-5g2h-9x5v-5h3x
- GitHub Advisory GHSA-j3gg-r6gp-95q2
- NVD CVE-2021-46871
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.