CVE-2020-17519
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.
- CVSS
- 7.5High
- Exploited in the wild
- Yes, in CISA KEV since 23 May 2024CISA deadline for US federal agencies: 13 Jun 2024public exploit code
- EPSS
- 98.0%chance of exploitation in the next 30 daystop 0.1% of scored CVEsFIRST score of 11 Nov 2026
- Fix
- Patch availablesee the advisories in the references
- Published
- 5 Jan 2021analysed here 12 Nov 2026
Do first. Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable. (CISA's required action for this KEV entry)
Summary
Triage
- Exploitable
- At runtime
- Attack vector
- network
- Weakness
- CWE-552 Common Weakness
The summary, impact and action text on this page are written by our AI analysis pipeline, or taken from the NVD description when a CVE was imported from NVD. They are not the vendor's wording: check them against the sources. A longer AI executive summary and technical analysis are generated for signed-in accounts on the Max plan.
Affected products
| Product | Affected versions | Vendor says fixed in |
|---|---|---|
| Apache Software Foundation Apache Flink | Apache Flink 1.11.0 to 1.11.2Vendor says fixed in: not stated |
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.
Products named in our analysis
- apache:flink
Fix and mitigation
WAF and other mitigations
Can a WAF block it? Partly. The bug can be reached over the network, so generic WAF rules may stop some attacks. Its weakness type is unknown, so we cannot be more precise.
Also consider: patch
Based on the weakness type only; no CVE-specific evidence yet. We check Cloudflare, AWS, Google Cloud Armor and Azure; for Akamai, Imperva, Fastly, F5, ask your vendor.
Remediation steps (AI-written)
Step-by-step remediation is generated for accounts on the Max plan, for CVEs that match a technology in their stack. Add this technology to your stack to see the fix checklist.
Exploitation evidence
- CISA KEV catalog
- Listed since 23 May 2024.
- CISA due date
- 13 Jun 2024, the remediation deadline for US federal agencies
- CISA required action
- Apply mitigations per vendor instructions or discontinue use of the product if mitigations are unavailable.
- Public exploit code
- Yes: 1 on Exploit-DB · 1 Metasploit module · 14 GitHub proofs of concept · 1 Nuclei template
- CISA SSVC
- exploitation active, automatable yes, technical impact partialAssessed by CISA 24 May 2024 (SSVC 2.0.3). Exploitation is none, poc (public proof of concept) or active.
Exploit-DB
- Apache Flink 1.11.0 - Unauthenticated Arbitrary File Read (Metasploit)webapps, 8 Jan 2021, verified by Exploit-DB
Metasploit
- auxiliary/scanner/http/apache_flink_jobmanager_traversalauxiliary, rank normal
Nuclei
- Apache Flink - Local File Inclusiondetection template, high
GitHub proofs of concept
- MrCl0wnLab/SimplesApachePathTraversal61 stars
- B1anda0/CVE-2020-1751947 stars
- murataydemir/CVE-2020-175198 stars
- dolevf/apache-flink-directory-traversal.nse3 stars
and 10 more repositories
Listed so you can judge urgency, not as a recommendation to run anything. GitHub “proofs of concept” are unvetted: some are fake or carry malware. Exploit-DB marks the entries its staff verified.
Timeline
- 5 Jan 2021Published
- 6 Jan 2021First public exploit or proof of conceptsame day later
- 23 May 2024Added to CISA KEV (exploited in the wild)1,233 days (about 3 years) later
- 24 May 2024CISA SSVC assessment: exploitation active2 days later
- 13 Jun 2024CISA remediation due date (US federal agencies)19 days later
- 21 Oct 2025CVE record last updated496 days (about 1 year) later
- 12 Nov 2026Analysed by vulneraibility.com387 days (about 1 year) later
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
| Metric | Value | What it means |
|---|---|---|
| Attack vector | NetworkReachable over the internet or any routable network. | Reachable over the internet or any routable network. |
| Attack complexity | LowRepeatable attack, no special conditions. | Repeatable attack, no special conditions. |
| Privileges required | NoneThe attacker needs no prior access. | The attacker needs no prior access. |
| User interaction | NoneNo victim action needed. | No victim action needed. |
| Scope | UnchangedImpact stays within the vulnerable component. | Impact stays within the vulnerable component. |
| Confidentiality | HighTotal data disclosure possible. | Total data disclosure possible. |
| Integrity | NoneNo unauthorised modification. | No unauthorised modification. |
| Availability | NoneThe service stays up. | The service stays up. |
Common questions
Is CVE-2020-17519 being exploited?
Yes. CVE-2020-17519 appears in CISA's Known Exploited Vulnerabilities catalog, which means exploitation in the wild has been confirmed and reported. Treat it as active rather than theoretical, and patch it ahead of higher-scoring vulnerabilities that carry no exploitation evidence.
How severe is CVE-2020-17519?
CVE-2020-17519 is rated High with a CVSS score of 7.5. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2020-17519?
Yes. A fix has been recorded for CVE-2020-17519. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2020-17519 affect?
CVE-2020-17519 affects apache:flink. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
References
17 references in the CVE record, grouped by the tags the record gives them.
Other links (17)
- lists.apache.org /thread.html/r6843202556a6d0bce9607ebc02e303f68fc88e9038235598bde3b50d%40%3Cdev.
- lists.apache.org /thread.html/r6843202556a6d0bce9607ebc02e303f68fc88e9038235598bde3b50d%40%3Cuser
- lists.apache.org /thread.html/r6843202556a6d0bce9607ebc02e303f68fc88e9038235598bde3b50d%40%3Canno
- openwall.com /lists/oss-security/2021/01/05/2
- lists.apache.org /thread.html/r28f17e564950d663e68cc6fe75756012dda62ac623766bb9bc5e7034%40%3Cissu
- packetstormsecurity.com /files/160849/Apache-Flink-1.11.0-Arbitrary-File-Read-Directory-Traversal.html
Show 11 more
- lists.apache.org /thread.html/r2fc60b30557e4a537c2a6293023049bd1c49fd92b518309aa85a0398%40%3Cissu
- lists.apache.org /thread.html/r4e1b72bfa789ea5bc20b8afe56119200ed25bdab0eb80d664fa5bfe2%40%3Cdev.
- lists.apache.org /thread.html/r0a433be10676f4fe97ca423d08f914e0ead341c901216f292d2bbe83%40%3Cissu
- lists.apache.org /thread.html/r88b55f3ebf1f8f4e1cc61f030252aaef4b77060b56557a243abb92a1%40%3Cissu
- lists.apache.org /thread.html/r88f427865fb6aa6e6378efe07632a1906b430365e15e3b9621aabe1d%40%3Cissu
- lists.apache.org /thread.html/ra8c96bf3ccb4e491f9ce87ba35f134b4449beb2a38d1ce28fd89001f%40%3Cdev.
- lists.apache.org /thread.html/r229167538863518738e02f4c1c5a8bb34c1d45dadcc97adf6676b0c1%40%3Cdev.
- lists.apache.org /thread.html/r90890afea72a9571d666820b2fe5942a0a5f86be406fa31da3dd0922%40%3Canno
- lists.apache.org /thread.html/r1125f3044a0946d1e7e6f125a6170b58d413ebd4a95157e4608041c7%40%3Canno
- lists.apache.org /thread.html/r26fcdd4fe288323006253437ebc4dd6fdfadfb5e93465a0e4f68420d%40%3Cuser
- cisa.gov /known-exploited-vulnerabilities-catalog?field_cve=CVE-2020-17519
Where the data on this page comes from
- CVE List (CVE.org): description, affected versions, references; CVE Terms of Use
- NVD: CVSS and CPE data
- CISA KEV catalog: exploitation, date added, due date
- CISA Vulnrichment (ADP): SSVC decision points
- FIRST EPSS: exploit probability and percentile
- Exploit-DB: published exploits
- Metasploit Framework: exploit and scanner modules
- Nuclei templates: detection templates
- PoC-in-GitHub: GitHub repositories that claim a proof of concept
Summary, impact and triage tags: written by our AI analysis pipeline from the sources above. Check them against the sources.
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