CASCACascade Atlas

Evidence dossier

CVE-2020-17519

Apache Flink directory traversal attack: reading remote files through the REST API

72.3–97.5Priority evidence range
As known Jul 19, 2026, 5:00 AM UTCgen-56ccdaf9

Normalized restatement

A change introduced in Apache Flink 1.11.0 (and released in 1.11.1 and 1.11.2 as well) allows attackers to read any file on the local filesystem of the JobManager through the REST interface of the JobManager process. Access is restricted to files accessible by the JobManager process. All users should upgrade to Flink 1.11.3 or 1.12.0 if their Flink instance(s) are exposed. The issue was fixed in commit b561010b0ee741543c3953306037f00d7a9f0801 from apache/flink:master.

State
PUBLISHED
Published
Jan 5, 2021
Updated
Oct 21, 2025
Evidence coverage
72%
CISA KEVCatalog member

Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.

FIRST EPSS97.86%

2026-07-18 · v2026.06.15 · percentile 99.9%

Source stateConflict visible

Distinct CVSS assessments remain side by side; none are averaged.

Source comparison

Who said what

apacheoriginal assertion
container

Apache Flink directory traversal attack: reading remote files through the REST API

CISA-ADPindependent enrichment
container

CISA ADP Vulnrichment

CVEderivative copy
container

CVE Program Container

CISA KEVoriginal assertion
observed_exploitation

Apache Flink Improper Access Control Vulnerability

FIRST EPSSoriginal assertion
model_probability

Probability 0.978560000000; percentile 0.999010000000

Applicability

Cited product scope

Trace impact →
apacheflink
[{"status": "affected", "version": "1.11.0", "versionType": "semver", "lessThanOrEqual": "1.11.2"}]unknown
Apache Software FoundationApache Flink
[{"status": "affected", "version": "Apache Flink 1.11.0 to 1.11.2"}]unknown
Unknown vendorUnknown product
cpe:2.3:a:apache:flink:*:*:*:*:*:*:*:*; start including 1.11.0; end excluding 1.11.3supported

Assessments

CVSS by origin

7.5
nvd@nist.govCVSS 3.1 · role PrimaryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
5.0
nvd@nist.govCVSS 2.0 · role PrimaryAV:N/AC:L/Au:N/C:P/I:N/A:N
9.1
134c704f-9b21-4f2e-91b3-4a467353bcc0CVSS 3.1 · role SecondaryCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
9.1
CISA-ADPCVSS 3.1 · role unknownCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H

Limitations and unknowns

  • KEV membership is authoritative for the catalog, not proof of exposure in any environment.
  • EPSS is a dated model probability and not an individual-environment prediction.
  • Affected or fixed status applies only to the exact cited product and version scope; unresolved scope remains unknown.
  • NVD-carried upstream facts remain derivative and are not independent corroboration.
  • Only NVD metrics validated under the generation-bound calculator are Public Priority eligible; direct CVE record metrics remain display-only.
  • NVD CVSS source eligibility is closed: NVD-authored, exact record-source, or registered same-CVE container origin; unmapped sources remain display-only.
  • Factor D is unknown in Public Core because no accepted canonical mapping-obligation ledger is present.
  • Core replay supports the active and immediately prior generation; retrospective valid-at replay is deferred.