Vulnerability · Published Apr 22, 2021 · Assigned by juniper

CVE-2021-0268Junos OS: J-Web has an Improper Neutralization of CRLF Sequences in its HTTP Headers which allows an attacker to carry out multiple types of attacks.

High 8.8

In plain English

A high-severity buffer overflow in Junos OS from Juniper Networks. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.9% (higher than 58% of all known vulnerabilities).

Severity (CVSS 3.1)8.8High
Exploit odds (30 days)0.9%top 41.5% of all CVEs
Exploited in the wildNo reportsnot in CISA KEV
Attack toolingNoneno public tooling known

Official description

An Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Response Splitting') weakness in J-web of Juniper Networks Junos OS leads to buffer overflows, segment faults, or other impacts, which allows an attacker to modify the integrity of the device and exfiltration information from the device without authentication. The weakness can be exploited to facilitate cross-site scripting (XSS), cookie manipulation (modifying session cookies, stealing cookies) and more. This weakness can also be exploited by directing a user to a seemingly legitimate link from the affected site. The attacker requires no special access or permissions to the device to carry out such attacks. This issue affects: Juniper Networks Junos OS: 18.1 versions prior to 18.1R3-S11; 18.2 versions prior to 18.2R3-S5; 18.3 versions prior to 18.3R2-S4, 18.3R3-S3; 18.4 versions prior to 18.4R2-S5, 18.4R3-S3; 19.1 versions prior to 19.1R2-S2, 19.1R3-S2; 19.2 versions prior to 19.2R1-S5, 19.2R2; 19.3 versions prior to 19.3R3; 19.4 versions prior to 19.4R1-S3, 19.4R2, 19.4R3; 20.1 versions prior to 20.1R1-S2, 20.1R2. This issue does not affect Juniper Networks Junos OS versions prior to 18.1R1.

Affected products (as reported)

VendorProductVersions
Juniper Networks Junos OS 18.1 – before 18.1R3-S1118.2 – before 18.2R3-S518.3 – before 18.3R2-S4, 18.3R3-S318.4 – before 18.4R2-S5, 18.4R3-S319.1 – before 19.1R2-S2, 19.1R3-S219.2 – before 19.2R1-S5, 19.2R219.3 – before 19.3R3

Weakness: CWE-113, CWE-120, CWE-79 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:L

References