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Full vulnerability report · 2017
CVE-2017-3803High confidence

n/a Cisco IOS: Missing Release of Resource after Effective Lifetime

Unknown · Cisco IOS

Official source article: Cisco CISCO-SA-20170118-CATALYST ↗. Check the applicable product and release in the original source.

4.7MediumCVSS 3.0
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Mitigation available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.56% for the current model date.

Compensating controls

  • Apply the linked authoritative mitigation while planning the permanent fix.
  • Restrict local access and enforce least privilege on affected hosts.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Unknown Cisco IOS and falls inside the recorded affected range.
  2. Recheck the vendor advisory before scheduling a change because no verified fixed version is currently retained.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2017-12920

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Mitigation available
01

What, why and how

A vulnerability in the Cisco IOS Software forwarding queue of Cisco 2960X and 3750X switches could allow an unauthenticated, adjacent attacker to cause a memory leak in the software forwarding queue that would eventually lead to a partial denial of service (DoS) condition. More Information: CSCva72252. Known Affected Releases: 15.2(2)E3 15.2(4)E1. Known Fixed Releases: 15.2(2)E6 15.2(4)E3 15.2(5)E1 15.2(5.3.28i)E1 15.2(6.0.49i)E 3.9(1)E.

What

A vulnerability in the Cisco IOS Software forwarding queue of Cisco 2960X and 3750X switches could allow an unauthenticated, adjacent attacker to cause a memory leak in the software forwarding queue that would eventually lead to a partial denial of service (DoS) condition. More Information: CSCva72252. Known Affected Releases: 15.2(2)E3 15.2(4)E1. Known Fixed Releases: 15.2(2)E6 15.2(4)E3 15.2(5)E1 15.2(5.3.28i)E1 15.2(6.0.49i)E 3.9(1)E.

Why

The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.

How

An attacker operating through the affected interface may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

What

A vulnerability in the Cisco IOS Software forwarding queue of Cisco 2960X and 3750X switches could allow an unauthenticated, adjacent attacker to cause a memory leak in the software forwarding queue that would eventually lead to a partial denial of service (DoS) condition. More Information: CSCva72252. Known Affected Releases: 15.2(2)E3 15.2(4)E1. Known Fixed Releases: 15.2(2)E6 15.2(4)E3 15.2(5)E1 15.2(5.3.28i)E1 15.2(6.0.49i)E 3.9(1)E.

Why

The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.

How

An attacker operating through the affected interface may attempt exploitation without authentication or user interaction. If successful, the issue may disrupt the affected service.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
the affected interface → Missing Release of Resource after Effective Lifetime → disrupt the affected service
Attack surface
Unspecified
Privileges required
None: unauthenticated exploitation is possible
User interaction
None
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Changed: exploitation can affect a different security authority
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-772 ↗

CWE-772: Missing Release of Resource after Effective Lifetime. The product does not release a resource after its effective lifetime has ended, i.e., after the resource is no longer needed.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L

Common Vulnerability Scoring System 3.0: the compact vector below is decoded into plain language.

AVAdjacentAttack vector: The attacker must be on an adjacent or logically close network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.PRNonePrivileges required: The attacker does not need an account or existing privileges.UINoneUser interaction: No action by another user is required.SChangedScope: The attack can affect a component governed by a different security authority.CNoneConfidentiality impact: No direct loss is represented by this metric.INoneIntegrity impact: No direct loss is represented by this metric.ALowAvailability impact: A successful attack can cause a limited loss.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
UnauthenticatedDenial of serviceCWE-772
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

Canadian Centre for Cyber Security · English · AV17-011Cisco Releases security updates

Cisco released multiple security updates to address vulnerabilities (critical to medium) in the following products. Cisco Hybrid Meeting Server Web Interface Cross-Site Request Forgery Vulnerability Cisco IOS and Cisco IOx Software Information Disclosure Vulnerability Cisco IOS for Catalyst 2960X and 3750X Switches Denial of Service Vulnerability Cisco Mobility Express 2800 and 3800 802.11 Denial of Service Vulnerability Cisco Mobility Express 2800 and 3800 Denial of Service Vulnerability Cisco NetFlow Generation Appliance Cross-Site Scripting Vulnerability Cisco Nexus 5000, 6000, and 7000 Series Switches Software IS-IS Packet Processing Denial of Service Vulnerability Cisco Unified Communications Manager Cross-Site Scripting Vulnerability Cisco WebEx Browser Extension Remote Code Execution Vulnerability Cisco WebEx Meeting Center Site Redirection Vulnerability Cisco WebEx Meetings Server Arbitrary Password Change Vulnerability Cisco WebEx Meetings Server Command Bypass Vulnerability Cisco WebEx Meetings Server Cross-Site Request Forgery Vulnerability Cisco WebEx Meetings Server Information Disclosure Vulnerability CVE References: Critical Impact CVE: CVE-2017-3823 Medium Impact CVEs: CVE-2016-9218, CVE-2016-9220, CVE-2016-9221, CVE-2016-9222, CVE-2017-3794, CVE-2017-3795, CVE-2017-3796, CVE-2017-3797, CVE-2017-3798, CVE-2017-3799, CVE-2017-3803, CVE-2017-3804, CVE-2017-3805

Official advisory ↗
JVN iPedia · Japanese · JVNDB-2017-001371Cisco 2960X および 3750X スイッチの Cisco IOS ソフトウェアの転送キューにおけるサービス運用妨害 (DoS) の脆弱性

Cisco 2960X および 3750X スイッチの Cisco IOS ソフトウェアの転送キューには、メモリリークにより、サービス運用妨害 (DoS) 状態にされる脆弱性が存在します。 ベンダは、本脆弱性を Bug ID CSCva72252 として公開しています。

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Mitigation available
Affected
Cisco IOS: Cisco IOS
Fixed
No fixed version is explicitly recorded in the structured CVE data.
Action
Apply the mitigation in the linked authoritative guidance while planning the vendor's permanent fix.
Workaround
A mitigation or workaround reference is available from the source linked below; validate it against the affected product and version.
04

Evidence and provenance

Published 26 Jan 2017 · Last source change 5 Aug 2024, 14:39 UTC · CWE-772 · Missing Release of Resource after Effective Lifetime

CVE recordCVE.org · 5.1
CVSS sourceNIST NVD
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-09-01
European sourceENISA EUVD · EUVD-2017-12920
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceNIST NVD
NVD statusNVD modified after enrichment

Missing structured fields: affected product. Missing data is not evidence of low risk; review the primary advisory.

Material change intelligence

What changed after publication

View recent updates ↗
  1. ENISA EUVD mappingEUVD-2017-12920 was added to the official ENISA EUVD mapping for this CVE.
    Before
    not recorded
    After
    {"euvdId":"EUVD-2017-12920"}
    ENISA EUVD ↗
  2. Vendor guidanceAuthoritative vendor guidance changed: added mitigation: tools.cisco.com/cisco-sa-20170118-catalyst; added remediation: tools.cisco.com/cisco-sa-20170118-catalyst.
    Before
    no authoritative guidance recorded
    After
    mitigation: tools.cisco.com/cisco-sa-20170118-catalyst · remediation: tools.cisco.com/cisco-sa-20170118-catalyst
    tools.cisco.com ↗
  3. Remediation statusRemediation status changed from Awaiting fix to Mitigation available.
    Before
    Awaiting fix
    After
    Mitigation available
    tools.cisco.com ↗
  4. SeveritySeverity changed from Unknown to Medium.
    Before
    Unknown
    After
    Medium
    NIST NVD ↗
  5. CVSS scoreCVSS score changed from not recorded to 4.7 (CVSS 3.0 · NIST NVD · CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L).
    Before
    not recorded
    After
    4.7 (CVSS 3.0 · NIST NVD · CVSS:3.0/AV:A/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:L)
    NIST NVD ↗
  6. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Mitigation reference recorded
ENISA EUVD · EUVD-2017-12920↗Mitigation reference · Cisco CISCO-SA-20170118-CATALYST↗CVE authority or vendor reference↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2017-3803 · cve.blacktree.nl