How severe is CVE-2017-16227?

CVE-2017-16227 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2017-16227 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 19% (97th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2017-16227?

CVE-2017-16227 primarily affects Quagga. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2017-16227?

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-2017-16227 published?

CVE-2017-16227 was published on 2017-10-29 and last updated on 2026-06-17.

CVE-2017-16227

CVE-2017-16227 is a high-severity vulnerability in Quagga with a CVSS 3.x base score of 7.5. Its EPSS exploit-prediction score of 19% places it in the 97th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
CVSS v2: 5.0
EPSS exploit prediction: 19% (97th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Quagga
Published: 2017-10-29
Last modified: 2026-06-17

Description

The aspath_put function in bgpd/bgp_aspath.c in Quagga before 1.2.2 allows remote attackers to cause a denial of service (session drop) via BGP UPDATE messages, because AS_PATH size calculation for long paths counts certain bytes twice and consequently constructs an invalid message.

Frequently asked questions

What is CVE-2017-16227?: The aspath_put function in bgpd/bgp_aspath.c in Quagga before 1.2.2 allows remote attackers to cause a denial of service (session drop) via BGP UPDATE messages, because AS_PATH size calculation for long paths counts certain bytes twice and consequently constructs an invalid message.
How severe is CVE-2017-16227?: CVE-2017-16227 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2017-16227 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 19% (97th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2017-16227?: CVE-2017-16227 primarily affects Quagga. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2017-16227?: 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-2017-16227 published?: CVE-2017-16227 was published on 2017-10-29 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:quagga:quagga:*:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*

More vulnerabilities in Quagga

CVE-2016-1245 — Critical (CVSS 9.8): It was discovered that the zebra daemon in Quagga before 1.0.20161017 suffered from a stack-based buffer overflow when…
CVE-2017-3224 — High (CVSS 8.2): Open Shortest Path First (OSPF) protocol implementations may improperly determine Link State Advertisement (LSA)…
CVE-2016-2342 — High (CVSS 8.1): The bgp_nlri_parse_vpnv4 function in bgp_mplsvpn.c in the VPNv4 NLRI parser in bgpd in Quagga before 1.0.20160309, when…
CVE-2021-44038 — High (CVSS 7.8): An issue was discovered in Quagga through 1.2.4. Unsafe chown/chmod operations in the suggested spec file allow users…
CVE-2018-5379 — High (CVSS 7.5): The Quagga BGP daemon (bgpd) prior to version 1.2.3 can double-free memory when processing certain forms of UPDATE…
CVE-2017-5495 — High (CVSS 7.5): All versions of Quagga, 0.93 through 1.1.0, are vulnerable to an unbounded memory allocation in the telnet 'vty' CLI,…

All CVEs affecting Quagga →

Other CWE-20 (Improper Input Validation) vulnerabilities

CVE-2026-48316 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48281 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48277 — Critical (CVSS 10.0): ColdFusion versions 2025.9, 2023.20 and earlier are affected by an Improper Input Validation vulnerability that could…
CVE-2026-48055 — Critical (CVSS 10.0): Streambert is a cross-platform Electron Desktop App to stream and download any video media. In versions 2.4.0 and…
CVE-2026-34910 — Critical (CVSS 10.0): A malicious actor with access to the network could exploit an Improper Input Validation vulnerability found in UniFi OS…
CVE-2026-33587 — Critical (CVSS 10.0): Lack of user input sanitisation in Open Notebook v1.8.3 allows the application user to execute Python code (and…

Browse all CWE-20 (Improper Input Validation) vulnerabilities →