How severe is CVE-2018-5381?

CVE-2018-5381 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2018-5381 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-5381?

CVE-2018-5381 primarily affects Quagga. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-5381?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2018-5381 published?

CVE-2018-5381 was published on 2018-02-19 and last updated on 2026-06-17.

CVE-2018-5381

CVE-2018-5381 is a medium-severity vulnerability in Quagga with a CVSS 3.x base score of 6.5. Its EPSS exploit-prediction score of 31% places it in the 98th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-835.

Key facts

Severity: Medium (CVSS 3.x base score 6.5)
CVSS v2: 5.0
EPSS exploit prediction: 31% (98th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: Quagga
Published: 2018-02-19
Last modified: 2026-06-17

Description

The Quagga BGP daemon (bgpd) prior to version 1.2.3 has a bug in its parsing of "Capabilities" in BGP OPEN messages, in the bgp_packet.c:bgp_capability_msg_parse function. The parser can enter an infinite loop on invalid capabilities if a Multi-Protocol capability does not have a recognized AFI/SAFI, causing a denial of service.

Frequently asked questions

What is CVE-2018-5381?: The Quagga BGP daemon (bgpd) prior to version 1.2.3 has a bug in its parsing of "Capabilities" in BGP OPEN messages, in the bgp_packet.c:bgp_capability_msg_parse function. The parser can enter an infinite loop on invalid capabilities if a Multi-Protocol capability does not have a recognized AFI/SAFI, causing a denial of service.
How severe is CVE-2018-5381?: CVE-2018-5381 has a CVSS 3.x base score of 6.5, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2018-5381 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 31% (98th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-5381?: CVE-2018-5381 primarily affects Quagga. In total, 8 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-5381?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-5381 published?: CVE-2018-5381 was published on 2018-02-19 and last updated on 2026-06-17.

References

Affected products (8)

cpe:2.3:a:quagga:quagga:*:*:*:*:*:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:14.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:16.04:*:*:*:lts:*:*:*
cpe:2.3:o:canonical:ubuntu_linux:17.10:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:7.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
cpe:2.3:o:siemens:ruggedcom_rox_ii_firmware:*:*:*:*:*:*:*:*

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