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CVE-2009-2055

Cisco IOS XR Border Gateway Protocol (BGP) Denial-of-Service

5.9 MEDIUMActively exploited (CISA KEV)EPSS 3.31%
  1. Published19 Aug 2009
  2. Added to CISA KEV25 Mar 2022
  3. Remediation due15 Apr 2022
Actively exploited (CISA KEV)

Cisco IOS XR,when BGP is the configured routing feature, allows remote attackers to cause a denial-of-service (DoS).

Added to KEV: 25 Mar 2022Federal remediation due: 15 Apr 2022

Description

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 3.1 breakdown

Attack vectorNetwork
Attack complexityHigh
Privileges requiredNone
User interactionNone
ScopeUnchanged
ConfidentialityNone
IntegrityNone
AvailabilityHigh
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

Cisco iOS XR3.4 · 3.4.0 · 3.4.1 · 3.4.2

Remediation

No fixed version is recorded in the NVD data. Check the vendor advisory for the latest guidance.

References

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Frequently asked

Is CVE-2009-2055 being actively exploited?

Yes. CVE-2009-2055 is listed in the CISA Known Exploited Vulnerabilities (KEV) catalog, added 25 Mar 2022.

How severe is CVE-2009-2055?

CVE-2009-2055 has a CVSS 3.1 base score of 5.9, rated medium. EPSS estimates a 3.31% probability of exploitation.

Which products are affected by CVE-2009-2055?

Affected products include Cisco iOS XR.

How do I fix CVE-2009-2055?

Apply the vendor's patch or advisory guidance, then verify no affected versions remain across your devices.

How Secuno handles this

Secuno correlates vulnerabilities like CVE-2009-2055 against the real software inventory on every managed device, every day. Rather than a static severity, each match is scored in context: exploit availability, EPSS, the asset's exposure, and business criticality decide where it lands in the queue. Because it is on the CISA KEV list, Secuno flags any affected asset as top-priority automatically. If an affected version is present anywhere across your portfolio, it surfaces automatically with a prioritised remediation path.

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Data from the NVD, CISA KEV catalog and FIRST EPSS. CVSS 3.1 base score shown where available.