How severe is CVE-2018-0256?

CVE-2018-0256 has a CVSS 3.x base score of 5.8, rated medium 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 low.

Is CVE-2018-0256 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2018-0256?

CVE-2018-0256 primarily affects Cisco Asr 5000 Series Software. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2018-0256?

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

When was CVE-2018-0256 published?

CVE-2018-0256 was published on 2018-04-19 and last updated on 2026-06-17.

CVE-2018-0256

CVE-2018-0256 is a medium-severity vulnerability in Cisco Asr 5000 Series Software with a CVSS 3.x base score of 5.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: Medium (CVSS 3.x base score 5.8)
CVSS v2: 5.0
EPSS exploit prediction: 2% (73rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Cisco Asr 5000 Series Software
Published: 2018-04-19
Last modified: 2026-06-17

Description

A vulnerability in the peer-to-peer message processing functionality of Cisco Packet Data Network Gateway could allow an unauthenticated, remote attacker to cause the Session Manager (SESSMGR) process on an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to incorrect validation of peer-to-peer packet headers. An attacker could exploit this vulnerability by sending a crafted peer-to-peer packet through an affected device. A successful exploit could allow the attacker to cause the SESSMGR process on the affected device to restart unexpectedly, which could briefly impact traffic while the SESSMGR process restarts and result in a DoS condition. Cisco Bug IDs: CSCvg88786.

Frequently asked questions

What is CVE-2018-0256?: A vulnerability in the peer-to-peer message processing functionality of Cisco Packet Data Network Gateway could allow an unauthenticated, remote attacker to cause the Session Manager (SESSMGR) process on an affected device to restart, resulting in a denial of service (DoS) condition. The vulnerability is due to incorrect validation of peer-to-peer packet headers. An attacker could exploit this vulnerability by sending a crafted peer-to-peer packet through an affected device. A successful exploit could allow the attacker to cause the SESSMGR process on the affected device to restart unexpectedly, which could briefly impact traffic while the SESSMGR process restarts and result in a DoS condition. Cisco Bug IDs: CSCvg88786.
How severe is CVE-2018-0256?: CVE-2018-0256 has a CVSS 3.x base score of 5.8, rated medium 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 low.
Is CVE-2018-0256 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (73rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2018-0256?: CVE-2018-0256 primarily affects Cisco Asr 5000 Series Software. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2018-0256?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2018-0256 published?: CVE-2018-0256 was published on 2018-04-19 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:o:cisco:asr_5000_series_software:20.3.0.66671:*:*:*:*:*:*:*
cpe:2.3:o:cisco:asr_5000_series_software:p2p_2.16.879:*:*:*:*:*:*:*

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