CVE-2012-5521

quagga (ospf6d) 0.99.21 has a DoS flaw in the way the ospf6d daemon performs routes removal

Published: 2019-11-25 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2012-5521 is rated Moderate Risk (51.9/100): CVSS Medium severity, with medium exploitation likelihood (EPSS 1.49%). EPSS rose +1.17% over the last day, indicating growing attacker interest. Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2012-5521

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.33% 1.49% +1.17%
2 2025-04-06 0.20% 0.33% +0.13%
3 2025-03-30 — 0.20% —

Full EPSS history (7 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2012-5521

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.5 3.1 MEDIUM
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Click to expand
Attack vector (AV:A)
Attacker has to be nearby on the network—same office, same link, that vibe—not the whole wide internet.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:N)
Data isn’t meaningfully altered or forged.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 3.6 [email protected]
3.3 2.0 LOW
AV:A/AC:L/Au:N/C:N/I:N/A:P Click to expand
Access vector (AV:A)
Requires access to an adjacent network segment.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:N)
No confidentiality impact.
Integrity impact (I:N)
No integrity impact.
Availability impact (A:P)
Partial availability impact.
 6.5 2.9 [email protected]

Weakness enumeration for CVE-2012-5521

OS Trackers for CVE-2012-5521

vendor priority summary link
redhat low — https://access.redhat.com/security/cve/CVE-2012-5521
ubuntu low CVE-2012-5521 low priority: Ubuntu including 1 source packages (quagga), 30 status rows across 30 suites (artful, bionic, cosmic, disco, eoan, focal, groovy, hirsute, impish, jammy, kinetic, lucid, lunar, mantic, noble, oracular, plucky, precise, quantal, questing, raring, saucy, trusty, upstream, utopic, vivid, wily, xenial, yakkety, zesty): ignored 17, DNE 9, deferred 3, needs-triage 1. https://ubuntu.com/security/CVE-2012-5521

Affected software / configurations for CVE-2012-5521

Vendor Product Version Raw CPE
quagga quagga 0.99.21 cpe:2.3:a:quagga:quagga:0.99.21:*:*:*:*:*:*:*
debian debian_linux 8.0 cpe:2.3:o:debian:debian_linux:8.0:*:*:*:*:*:*:*
debian debian_linux 9.0 cpe:2.3:o:debian:debian_linux:9.0:*:*:*:*:*:*:*
debian debian_linux 10.0 cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
redhat enterprise_linux 5.0 cpe:2.3:o:redhat:enterprise_linux:5.0:*:*:*:*:*:*:*
redhat enterprise_linux 6.0 cpe:2.3:o:redhat:enterprise_linux:6.0:*:*:*:*:*:*:*

References for CVE-2012-5521

cvelogic Threat Intelligence