// For flags

CVE-2021-29991

 

Severity Score

8.1
*CVSS v3.1

Exploit Likelihood

*EPSS

Affected Versions

*CPE

Public Exploits

0
*Multiple Sources

Exploited in Wild

-
*KEV

Decision

-
*SSVC
Descriptions

Firefox incorrectly accepted a newline in a HTTP/3 header, interpretting it as two separate headers. This allowed for a header splitting attack against servers using HTTP/3. This vulnerability affects Firefox < 91.0.1 and Thunderbird < 91.0.1.

Firefox aceptaba incorrectamente una nueva línea en un encabezado HTTP/3, interpretándola como dos encabezados separados. Esto permitía un ataque de división de encabezados contra servidores que usaban HTTP/3. Esta vulnerabilidad afecta a Firefox versiones anteriores a 91.0.1 y Thunderbird versiones anteriores a 91.0.1

*Credits: N/A
CVSS Scores
Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
None
Attack Vector
Network
Attack Complexity
Medium
Authentication
None
Confidentiality
Partial
Integrity
Partial
Availability
None
* Common Vulnerability Scoring System
SSVC
  • Decision:-
Exploitation
-
Automatable
-
Tech. Impact
-
* Organization's Worst-case Scenario
Timeline
  • 2021-04-01 CVE Reserved
  • 2021-11-03 CVE Published
  • 2024-07-19 EPSS Updated
  • 2024-08-03 CVE Updated
  • ---------- Exploited in Wild
  • ---------- KEV Due Date
  • ---------- First Exploit
CWE
  • CWE-444: Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')
CAPEC
References (1)
Affected Vendors, Products, and Versions
Vendor Product Version Other Status
Vendor Product Version Other Status <-- --> Vendor Product Version Other Status
Mozilla
Search vendor "Mozilla"
Firefox
Search vendor "Mozilla" for product "Firefox"
< 91.0.1
Search vendor "Mozilla" for product "Firefox" and version " < 91.0.1"
-
Affected
Mozilla
Search vendor "Mozilla"
Thunderbird
Search vendor "Mozilla" for product "Thunderbird"
< 91.0.1
Search vendor "Mozilla" for product "Thunderbird" and version " < 91.0.1"
-
Affected