CVE-2009-2055

MEDIUMNVD 5.99.0▲Trending — 4 sources updated this weekExploited in the wild

5.9

Cisco IOS XR 3.4.0 through 3.8.1 allows remote attackers to cause a denial of service (session reset) via a BGP UPDATE message with an invalid attribute, as demonstrated in the wild on 17 August 2009.

CVSS v3: 5.9
EG Score: 9.0(high)
EPSS: 73.9%
KEV: ⚠ Exploited

Published

August 19, 2009

Last Modified

April 22, 2026

Advisory Details (2)

Auto-updated May 20, 2026

⚠️ Active exploitation confirmed. Patch available. Sources: cisa.

cisa Patch Available🔴 Active Exploitation

Known Exploited Vulnerabilities Catalog | CISA

Known Exploited Vulnerabilities Catalog | CISA. Listed in CISA Known Exploited Vulnerabilities catalog.

https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2009-2055

generic

http://securitytracker.com/id?1022739

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

CWE-20Improper Input Validation

Data Freshness Timeline

(refreshed 20× in last 7d / 20× in last 30d)

Every time one of our enrichment pipelines (NVD, MITRE cvelistV5, EPSS, CISA KEV, GHSA, OSV, vendor advisories) ran against this CVE. Most recent first.

2026-06-04 22:02 UTCEG score recompute
2026-06-04 22:02 UTCGHSA enrichment
2026-06-04 18:10 UTCEG score recompute
2026-06-04 18:10 UTCGHSA enrichment
2026-06-04 14:18 UTCEG score recompute
2026-06-04 14:18 UTCGHSA enrichment
2026-06-04 13:09 UTCepss_batch
2026-06-04 13:09 UTCepss_batch
2026-06-04 10:26 UTCEG score recompute
2026-06-04 10:26 UTCGHSA enrichment
2026-06-04 06:33 UTCEG score recompute
2026-06-04 06:33 UTCGHSA enrichment
2026-06-04 02:41 UTCEG score recompute
2026-06-04 02:41 UTCGHSA enrichment
2026-06-03 22:49 UTCEG score recompute
2026-06-03 22:49 UTCGHSA enrichment
2026-06-03 19:09 UTCkev_newly_listed
2026-06-03 18:57 UTCEG score recompute
2026-06-03 18:57 UTCGHSA enrichment
2026-06-03 15:05 UTCEG score recompute

Frequently asked(6)

What is CVE-2009-2055?

CVE-2009-2055 is a medium vulnerability published on August 19, 2009. Cisco IOS XR 3.4.0 through 3.8.1 allows remote attackers to cause a denial of service (session reset) via a BGP UPDATE message with an invalid attribute, as demonstrated in the wild on 17 August 2009.

When was CVE-2009-2055 disclosed?

CVE-2009-2055 was first published in the National Vulnerability Database on August 19, 2009, with the most recent update on April 22, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.

Is CVE-2009-2055 actively exploited?

Yes. CISA added CVE-2009-2055 to the Known Exploited Vulnerabilities catalog on March 25, 2022, affecting Cisco IOS XR. KEV listing indicates confirmed exploitation in the wild; this CVE warrants immediate patching attention.

What is the CVSS score of CVE-2009-2055?

CVE-2009-2055 has a CVSS v3 base score of 5.9 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 9.0.

Which products are affected by CVE-2009-2055?

CVE-2009-2055 affects Cisco IOS XR. The full affected-products list, including version ranges and fixed versions, is shown in the Affected Packages section of this page.

How do I remediate CVE-2009-2055?

Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2009-2055, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2009-2055

Explore →

Is Your Infrastructure Affected by CVE-2009-2055?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs

CVE-2009-2055

📅 Published

🔄 Last Modified

📋 Advisory Details (2)

Known Exploited Vulnerabilities Catalog | CISA

Weakness Classification(1)

Data Freshness Timeline

❓ Frequently asked(6)

Dependency Blast Radius

Is Your Infrastructure Affected by CVE-2009-2055?

🔗 Related CVEs(same CWE)

Same CWE

Published

Last Modified

Advisory Details (2)

Frequently asked(6)

Related CVEs(same CWE)