Cisco Elastic Services Controller REST API Authentication Bypass Vulnerability
A vulnerability in the REST API of Cisco Elastic Services Controller (ESC) could allow an unauthenticated, remote attacker to bypass authentication on the REST API. The vulnerability is due to improper validation of API requests. An attacker could exploit this vulnerability by sending a crafted request to the REST API. A successful exploit could allow the attacker to execute arbitrary actions through the REST API with administrative privileges on an affected system.
- Published
- May 10, 2019
- Updated
- Jun 16, 2026
- EPSS
- 30.3% · 98th percentile
- CWE
- CWE-287
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Report tools
Action score
49
Plan
Add it to your regular patch cycle.
- CVSS
- 40 / 40 · 10.0 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 9 / 30 · 30.3%
CISA SSVC decision
- Exploitation
- none
- Automatable
- yes
- Technical impact
- total
Vulnrichment: CISA's decision-tree inputs.
CNA vs NVD score
- NVD
- 10.0
- CNA · cisco
- 10.0
- agree
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Affected systems
| Vendor | Product | CPE |
|---|---|---|
| cisco | elastic services controller | cpe:2.3:a:cisco:elastic_services_controller |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- cisco elastic services controller4.1 and later · before 4.5
Versions reported by the vendor
Affected version ranges reported by the assigning authority (cisco). Independent of NVD's CPE analysis and usually ahead of it.
Cisco Cisco Elastic Services Controller
- unspecified and later · before 4.1.0.100affected
- unspecified and later · before 4.2.0.74affected
- unspecified and later · before 4.3.0.121affected
- unspecified and later · before 4.4.0.80affected
Same product
cisco: all recordsOther highest-scoring records for the same primary product.
- CVE-2018-0121A vulnerability in the authentication functionality of the web-based service portal of Cisco Elastic Services Controller Software could allo40Plan
- CVE-2017-6713A vulnerability in the Play Framework of Cisco Elastic Services Controller (ESC) could allow an unauthenticated, remote attacker to gain ful40Plan
- CVE-2017-6683A vulnerability in the esc_listener.py script of Cisco Elastic Services Controllers could allow an authenticated, remote attacker to execute37Monitor
- CVE-2017-6712A vulnerability in certain commands of Cisco Elastic Services Controller could allow an authenticated, remote attacker to elevate privileges36Monitor
- CVE-2017-6688A vulnerability in Cisco Elastic Services Controllers could allow an authenticated, remote attacker to log in to an affected system as the L36Monitor
- CVE-2017-6684A vulnerability in Cisco Elastic Services Controllers could allow an authenticated, remote attacker to log in to an affected system as the L36Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
No fix version is recorded for this entry. Check the references for vendor advisories.
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
No commit or PR link among the references.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- No account or password is required.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- high · data can be read
- Integrity
- high · data or configuration can be modified
- Availability
- high · the service can be disrupted
Impact can extend beyond the vulnerable component (scope changes).
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Changed
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
Weakness class (CWE)
CWE-287 · Improper AuthenticationCVSS vector
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H
nvd-primary
Root cause
Authentication is added route by route instead of being enforced in one place. When a route added later bypasses the shared middleware, the session check never runs for it.
The bug in code
The whole CWE-287 classA representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.
Vulnerable
app.use("/admin", requireSession, adminRouter);
// Route added later skips the middlewareapp.post("/admin-api/config", updateConfig);Fixed
const admin = express.Router();admin.use(requireSession, requireRole("admin"));
admin.post("/config", updateConfig);app.use("/admin", admin);Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Attack patterns (CAPEC)
- Authentication AbuseCAPEC-114Medium
- Authentication BypassCAPEC-115Medium
- Identity SpoofingCAPEC-151likelihood: Medium · Medium
- Fake the Source of DataCAPEC-194Medium
- Exploiting Trust in ClientCAPEC-22likelihood: High · High
- Utilizing REST's Trust in the System Resource to Obtain Sensitive DataCAPEC-57likelihood: Medium · Very High
- Session HijackingCAPEC-593likelihood: High · Very High
- Token ImpersonationCAPEC-633Medium
ATT&CK techniques
Noroxi analysis
No Noroxi analysis for this record yet
We don't hand-write analysis for all 385,000+ vulnerabilities; that wouldn't be honest. For notable, high-impact vulnerabilities our team writes the mechanism, detection and remediation steps.
We use this product, ask for helpChange log
No changes recorded on tracked fields yet. Score, KEV, exploit maturity and fix status changes appear here.
References
Vendor advisories and official records. Exploit/PoC links are deliberately left out.