CVE-2021-31383: juniper networks junos os Stack-based Buffer Overflow
Vulnerability summary
CVE-2021-31383 is a high (CVSS 7.5) Stack-based Buffer Overflow vulnerability in juniper networks junos os. EPSS estimates a 1.01% chance of exploitation in the next 30 days, higher than 62.3% of scored vulnerabilities.
Timeline
- 19-10-2021PublishedVulnerability first disclosed.
- 16-09-2024Last modifiedVulnerability information updated.
Description
In Point to MultiPoint (P2MP) scenarios within established sessions between network or adjacent neighbors the improper use of a source to destination copy write operation combined with a Stack-based Buffer Overflow on certain specific packets processed by the routing protocol daemon (RPD) of Juniper Networks Junos OS and Junos OS Evolved sent by a remote unauthenticated network attacker causes the RPD to crash causing a Denial of Service (DoS). Continued receipt and processing of these packets will create a sustained Denial of Service (DoS) condition. This issue affects: Juniper Networks Junos OS 19.2 versions prior to 19.2R3-S2; 19.3 versions prior to 19.3R2-S6, 19.3R3-S2; 19.4 versions prior to 19.4R1-S4, 19.4R2-S4, 19.4R3-S3; 20.1 versions prior to 20.1R2-S2, 20.1R3; 20.2 versions prior to 20.2R2-S3, 20.2R3; 20.3 versions prior to 20.3R2. This issue does not affect Juniper Networks Junos OS versions prior to 19.2R1. Juniper Networks Junos OS Evolved 20.1 versions prior to 20.1R3-EVO; 20.2 versions prior to 20.2R3-EVO; 20.3 versions prior to 20.3R2-EVO.
CVSS metrics
3 scores · 2 sources · 2 versions- NVDNIST7.5HighCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
1.01%
Chance of exploitation in the next 30 days
Percentile
62%
Versus all other CVEs
30-day change
0.00 pp
From 1.01% on 18-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root cause- CWE-121Stack-based Buffer OverflowA stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function).
- CWE-787Out-of-bounds WriteThe product writes data past the end, or before the beginning, of the intended buffer.
Affected systems
Juniper2 products
- junos19.2 | 19.2:r1 | 19.2:r1-s1 | 19.2:r1-s2 | 19.2:r1-s3 | 19.2:r1-s4 | 19.2:r1-s5 | 19.2:r1-s6 | 19.2:r2 | 19.2:r2-s1 | 19.2:r3 | 19.2:r3-s1 | 19.3 | 19.3:r1 | 19.3:r1-s1 | 19.3:r2 | 19.3:r2-s1 | 19.3:r2-s2 | 19.3:r2-s3 | 19.3:r2-s4 | 19.3:r2-s5 | 19.3:r3 | 19.3:r3-s1 | 19.4:r1 | 19.4:r1-s1 | 19.4:r1-s2 | 19.4:r1-s3 | 19.4:r2 | 19.4:r2-s1 | 19.4:r2-s2 | 19.4:r2-s3 | 19.4:r3 | 19.4:r3-s1 | 19.4:r3-s2 | 20.1:r1 | 20.1:r1-s1 | 20.1:r1-s2 | 20.1:r1-s3 | 20.1:r1-s4 | 20.1:r2 | 20.1:r2-s1 | 20.2:r1 | 20.2:r1-s1 | 20.2:r1-s2 | 20.2:r1-s3 | 20.2:r2 | 20.2:r2-s1 | 20.2:r2-s2 | 20.3:r1 | 20.3:r1-s1
- junos_os_evolved20.1 | 20.1:r1 | 20.1:r1-s1 | 20.1:r2 | 20.1:r2-s1 | 20.1:r2-s2 | 20.1:r2-s3 | 20.1:r2-s4 | 20.1:r2-s5 | 20.2 | 20.2:r1 | 20.2:r1-s1 | 20.2:r2 | 20.2:r2-s1 | 20.3 | 20.3:r1 | 20.3:r1-s1 | 20.3:r1-s2 | 20.3:r1-s3
Juniper networks2 products
- junos os≥ 19.2, < 19.2R3-S2 | ≥ 19.3, < 19.3R2-S6, 19.3R3-S2 | ≥ 19.4, < 19.4R1-S4, 19.4R2-S4, 19.4R3-S3 | ≥ 20.1, < 20.1R2-S2, 20.1R3 | ≥ 20.2, < 20.2R2-S3, 20.2R3 | ≥ 20.3, < 20.3R2
- junos os evolved≥ 20.1, < 20.1R3-EVO | ≥ 20.2, < 20.2R3-EVO | ≥ 20.3, < 20.3R2-EVO
2 vendors · 4 products