CVE-2020-1641
Junos OS: A race condition on receipt of crafted LLDP packets leads to a memory leak and an LLDP crash.
A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an attacker to cause LLDP to crash leading to a Denial of Service (DoS). This issue occurs when crafted LLDP packets are received by the device from an adjacent device. Multiple LACP flaps will occur after LLDP crashes. An indicator of compromise is to evaluate log file details for lldp with RLIMIT. Intervention should occur before 85% threshold of used KB versus maximum available KB memory is reached. show log messages | match RLIMIT | match lldp | last 20 Matching statement is " /kernel: %KERNEL-[number]: Process ([pid #],lldpd) has exceeded 85% of RLIMIT_DATA: " with [] as variable data to evaluate for. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D95; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S7, 18.2R3; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.
Attack profile
How easy it is to exploit
- Attack vector
- Adjacent network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- None
- Integrity
- None
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
6.5
Junos OS: A race condition on receipt of crafted LLDP packets leads to a memory leak and an LLDP crash.
A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an attacker to cause LLDP to crash leading to a Denial of Service (DoS). This issue occurs when crafted LLDP packets are received by the device from an adjacent device. Multiple LACP flaps will occur after LLDP crashes. An indicator of compromise is to evaluate log file details for lldp with RLIMIT. Intervention should occur before 85% threshold of used KB versus maximum available KB memory is reached. show log messages | match RLIMIT | match lldp | last 20 Matching statement is " /kernel: %KERNEL-[number]: Process ([pid #],lldpd) has exceeded 85% of RLIMIT_DATA: " with [] as variable data to evaluate for. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D95; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S7, 18.2R3; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.
- Record
CVE-2020-1641- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Weakness
- CWE-362
- Updated
- 2026-11-02
EUVDEUVD-2020-12507
6.5
A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an attacker to cause LLDP to crash leading to a Denial of Service (DoS). This issue occurs when crafted LLDP packets are received by the device from an adjacent device. Multiple LACP flaps will occur after LLDP crashes. An indicator of compromise is to evaluate log file details for lldp with RLIMIT. Intervention should occur before 85% threshold of used KB versus maximum available KB memory is reached. show log messages | match RLIMIT | match lldp | last 20 Matching statement is " /kernel: %KERNEL-[number]: Process ([pid #],lldpd) has exceeded 85% of RLIMIT_DATA: " with [] as variable data to evaluate for. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D95; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S7, 18.2R3; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.
- Record
EUVD-2020-12507- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - Updated
- 2026-11-03
GitHub AdvisoriesGHSA-34rw-6hrg-mxr5 No score
A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an...
A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an attacker to cause LLDP to crash leading to a Denial of Service (DoS). This issue occurs when crafted LLDP packets are received by the device from an adjacent device. Multiple LACP flaps will occur after LLDP crashes. An indicator of compromise is to evaluate log file details for lldp with RLIMIT. Intervention should occur before 85% threshold of used KB versus maximum available KB memory is reached. show log messages | match RLIMIT | match lldp | last 20 Matching statement is " /kernel: %KERNEL-[number]: Process ([pid #],lldpd) has exceeded 85% of RLIMIT_DATA: " with [] as variable data to evaluate for. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D95; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S7, 18.2R3; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.
- Record
GHSA-34rw-6hrg-mxr5- Weakness
- CWE-362
- Updated
- 2026-11-02
NVD
6.5
A Race Condition vulnerability in Juniper Networks Junos OS LLDP implementation allows an attacker to cause LLDP to crash leading to a Denial of Service (DoS). This issue occurs when crafted LLDP packets are received by the device from an adjacent device. Multiple LACP flaps will occur after LLDP crashes. An indicator of compromise is to evaluate log file details for lldp with RLIMIT. Intervention should occur before 85% threshold of used KB versus maximum available KB memory is reached. show log messages | match RLIMIT | match lldp | last 20 Matching statement is " /kernel: %KERNEL-[number]: Process ([pid #],lldpd) has exceeded 85% of RLIMIT_DATA: " with [] as variable data to evaluate for. This issue affects: Juniper Networks Junos OS: 12.3 versions prior to 12.3R12-S15; 12.3X48 versions prior to 12.3X48-D95; 15.1 versions prior to 15.1R7-S6; 15.1X49 versions prior to 15.1X49-D200; 15.1X53 versions prior to 15.1X53-D593; 16.1 versions prior to 16.1R7-S7; 17.1 versions prior to 17.1R2-S11, 17.1R3-S2; 17.2 versions prior to 17.2R1-S9, 17.2R3-S3; 17.3 versions prior to 17.3R2-S5, 17.3R3-S6; 17.4 versions prior to 17.4R2-S4, 17.4R3; 18.1 versions prior to 18.1R3-S5; 18.2 versions prior to 18.2R2-S7, 18.2R3; 18.2X75 versions prior to 18.2X75-D12, 18.2X75-D33, 18.2X75-D50, 18.2X75-D420; 18.3 versions prior to 18.3R1-S7, 18.3R2-S3, 18.3R3; 18.4 versions prior to 18.4R1-S5, 18.4R2; 19.1 versions prior to 19.1R1-S4, 19.1R2.
- Record
CVE-2020-1641- CVSS 3.1
- 6.5 Medium
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H - CVSS 2.0
- 3.3 Low
AV:A/AC:L/Au:N/C:N/I:N/A:P - Weakness
- CWE-362
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases, published | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2020-1641 is a medium vulnerability (CVSS 6.5) in Juniper Junos, published July 17, 2020. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.40%, the 34th percentile. No source names a fixed version.