CVE-2021-43808: laravel framework Cross-site Scripting
Vulnerability summary
CVE-2021-43808 is a medium (CVSS 6.1) Cross-site Scripting vulnerability in laravel framework. EPSS estimates a 0.83% chance of exploitation in the next 30 days, higher than 56.6% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 07-12-2021PublishedVulnerability first disclosed.
- 04-08-2024Last modifiedVulnerability information updated.
Description
Laravel is a web application framework. Laravel prior to versions 8.75.0, 7.30.6, and 6.20.42 contain a possible cross-site scripting (XSS) vulnerability in the Blade templating engine. A broken HTML element may be clicked and the user taken to another location in their browser due to XSS. This is due to the user being able to guess the parent placeholder SHA-1 hash by trying common names of sections. If the parent template contains an exploitable HTML structure an XSS vulnerability can be exposed. This vulnerability has been patched in versions 8.75.0, 7.30.6, and 6.20.42 by determining the parent placeholder at runtime and using a random hash that is unique to each request.
CVSS metrics
4 scores · 3 sources · 2 versions- CVE.orgCNA5.3MediumCVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:N/I:H/A:NDiffers
- OSV · DebianEcosystem advisory · calculated6.1MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
EPSS trend
Probability
0.83%
Chance of exploitation in the next 30 days
Percentile
57%
Versus all other CVEs
30-day change
+0.03 pp
From 0.80% on 19-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundFramework
Maturity: poc
Weaknesses
CWE · root cause- CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
- CWE-327Use of a Broken or Risky Cryptographic AlgorithmThe product uses a broken or risky cryptographic algorithm or protocol.
Affected systems
Debian1 product
- php-laravel-framework< 6.20.14+dfsg-3
Laravel1 product
- framework< 6.20.42 | ≥ 7.0.0, < 7.30.6 | ≥ 8.0.0, < 8.75.0
2 vendors · 2 products
References
9 links- github.com/laravel/framework/security/advisories/GHSA-66hf-2p6w-jqfwX Refsource CONFIRMExploitThird Party Advisory
- github.com/laravel/framework/commit/b8174169b1807f36de1837751599e2828ceddb9bX Refsource MISCPatchThird Party Advisory
