How severe is CVE-2019-1846?

CVE-2019-1846 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2019-1846 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2019-1846?

CVE-2019-1846 affects Cisco Ios Xr. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2019-1846?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2019-1846 published?

CVE-2019-1846 was published on 2019-05-16 and last updated on 2026-06-17.

CVE-2019-1846

CVE-2019-1846 is a high-severity vulnerability in Cisco Ios Xr with a CVSS 3.x base score of 7.4. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.4)
CVSS v2: 6.1
EPSS exploit prediction: 1% (46th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Ios Xr
Published: 2019-05-16
Last modified: 2026-06-17

Description

A vulnerability in the Multiprotocol Label Switching (MPLS) Operations, Administration, and Maintenance (OAM) implementation of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to the incorrect handling of certain MPLS OAM packets. An attacker could exploit this vulnerability by sending malicious MPLS OAM packets to an affected device. A successful exploit could allow the attacker to cause the lspv_server process to crash. The crash could lead to system instability and the inability to process or forward traffic though the device, resulting in a DoS condition that require manual intervention to restore normal operating conditions.

Frequently asked questions

What is CVE-2019-1846?: A vulnerability in the Multiprotocol Label Switching (MPLS) Operations, Administration, and Maintenance (OAM) implementation of Cisco IOS XR Software for Cisco ASR 9000 Series Aggregation Services Routers could allow an unauthenticated, adjacent attacker to trigger a denial of service (DoS) condition on an affected device. The vulnerability is due to the incorrect handling of certain MPLS OAM packets. An attacker could exploit this vulnerability by sending malicious MPLS OAM packets to an affected device. A successful exploit could allow the attacker to cause the lspv_server process to crash. The crash could lead to system instability and the inability to process or forward traffic though the device, resulting in a DoS condition that require manual intervention to restore normal operating conditions.
How severe is CVE-2019-1846?: CVE-2019-1846 has a CVSS 3.x base score of 7.4, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2019-1846 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (46th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2019-1846?: CVE-2019-1846 affects Cisco Ios Xr. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2019-1846?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2019-1846 published?: CVE-2019-1846 was published on 2019-05-16 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:o:cisco:ios_xr:5.3.3:sp10:*:*:*:*:*:*

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