CVE-2020-17523

CRITICALNVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

This critical-severity CVE scores 9.8 under NVD CVSS v3. EPSS exploit probability: 85.9%, top 0% of all CVEs by exploit prediction. GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).

Triggered by: NVD CVSS baseline
Sources: epss, nvd
Trending — 3 sources updated this weekElevated
9.8
EchelonGraph verdictPatch this weekExploitation is likely or a public exploit exists.
  • High exploitation likelihood — EPSS 86%
CISA-KEV: Not listedEPSS: 86%CVSS: 9.8Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

Apache Shiro before 1.7.1, when using Apache Shiro with Spring, a specially crafted HTTP request may cause an authentication bypass.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
83(Track*)
EG Risk 83/100SSVC: Track*

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation86% × 40%
Automatability30% × 15%
Action: Watch closely — could escalate to Attend.
EPSS
99.7%
KEV
Not listed

Published

February 3, 2021

Last Modified

November 21, 2024

Advisory Details (8)

Auto-updated Jun 11, 2026
No patch confirmed yet.
generic
https://lists.apache.org/thread.html/r679ca97813384bdb1a4c087810ba44d9ad9c7c11583979bb7481d196%40%3Cdev.shiro.apache.org%3E
generic
https://lists.apache.org/thread.html/r5b93ddf97e2c4cda779d22fab30539bdec454cfa5baec4ad0ffae235%40%3Cgitbox.activemq.apache.org%3E
generic
https://lists.apache.org/thread.html/re25b8317b00a50272a7252c4552cf1a81a97984cc2111ef7728e48e0%40%3Cdev.shiro.apache.org%3E
generic
https://lists.apache.org/thread.html/rd4b613e121438b97e3eb263cac3137caddb1dbd8f648b73a4f1898a6%40%3Cissues.activemq.apache.org%3E
generic
https://lists.apache.org/thread.html/rce5943430a6136d37a1f2fc201d245fe094e2727a0bc27e3b2d43a39%40%3Cdev.shiro.apache.org%3E
generic
https://lists.apache.org/thread.html/r9d93dfb5df016b1a71a808486bc8f9fbafebbdbc8533625f91253f1d%40%3Cdev.shiro.apache.org%3E
generic
https://lists.apache.org/thread.html/r852971e28f54cafa7d325bd7033115c67d613b112a2a1076817390ac%40%3Cdev.shiro.apache.org%3E
generic
https://lists.apache.org/thread.html/r8244fd0831db894d5e89911ded9c72196d395a90ae655414d23ed0dd%40%3Cusers.activemq.apache.org%3E

Affected Packages

(3 across 1 ecosystem)
Maven(3)
PackageVulnerable rangeFixed inDependents
org.apache.shiro:shiro-spring1.0.0-incubating ... 1.7.0 (22 versions)1.7.1—
org.apache.shiro:shiro-spring-boot-starter1.4.0 ... 1.7.0 (10 versions)1.7.1—
org.apache.shiro:shiro-web1.0.0-incubating ... 1.7.0 (22 versions)1.7.1—

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 9× in last 7d / 20× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-23 01:50 UTCEG score recompute
  2. 2026-07-22 22:36 UTCEG score recompute
  3. 2026-07-22 14:05 UTCEPSS rescore
  4. 2026-07-21 15:22 UTCEPSS rescore
  5. 2026-07-21 15:22 UTCEPSS rescore
  6. 2026-07-20 17:04 UTCEPSS rescore
  7. 2026-07-20 17:04 UTCEPSS rescore
  8. 2026-07-19 02:52 UTCOSV refresh
  9. 2026-07-18 10:02 UTCEPSS rescore
  10. 2026-07-15 16:55 UTCEPSS rescore
  11. 2026-07-12 05:44 UTCEPSS rescore
  12. 2026-07-07 13:43 UTCEPSS rescore
  13. 2026-07-07 13:43 UTCEPSS rescore
  14. 2026-07-01 15:03 UTCEPSS rescore
  15. 2026-07-01 09:48 UTCOSV refresh
  16. 2026-06-25 13:47 UTCEPSS rescore
  17. 2026-06-24 14:03 UTCEPSS rescore
  18. 2026-06-24 14:03 UTCEPSS rescore
  19. 2026-06-23 21:31 UTCEPSS rescore
  20. 2026-06-23 21:31 UTCEPSS rescore
  21. 2026-06-15 17:46 UTCEPSS rescore
  22. 2026-06-13 22:58 UTCEPSS rescore
  23. 2026-06-13 22:58 UTCEPSS rescore
  24. 2026-06-13 15:13 UTCOSV refresh
  25. 2026-06-12 23:10 UTCEPSS rescore
Show 18 more
  1. 2026-06-11 13:58 UTCEPSS rescore
  2. 2026-06-10 22:16 UTCEPSS rescore
  3. 2026-06-10 22:16 UTCEPSS rescore
  4. 2026-06-10 13:20 UTCEPSS rescore
  5. 2026-06-07 15:23 UTCEPSS rescore
  6. 2026-06-07 15:23 UTCEPSS rescore
  7. 2026-06-05 22:45 UTCEPSS rescore
  8. 2026-06-05 22:45 UTCEPSS rescore
  9. 2026-06-01 13:50 UTCEPSS rescore
  10. 2026-06-01 13:50 UTCEPSS rescore
  11. 2026-05-31 00:15 UTCEPSS rescore
  12. 2026-05-31 00:15 UTCEPSS rescore
  13. 2026-05-29 13:42 UTCEPSS rescore
  14. 2026-05-28 13:43 UTCEPSS rescore
  15. 2026-05-28 13:43 UTCEPSS rescore
  16. 2026-05-26 21:22 UTCEG score recompute
  17. 2026-05-26 07:17 UTCEPSS rescore
  18. 2026-05-26 07:17 UTCEPSS rescore

Publicly available exploits

(1 reference)

Working exploit code is in the public domain (1 GitHub PoC). Defenders should treat patch urgency accordingly — public PoCs typically lead to mass-exploitation within 24-72 hours.

  • GitHub PoCjweny/shiro-cve-2020-17523
    First seen Feb 3, 2021

    shiro-cve-2020-17523 漏洞的两种绕过姿势分析 以及配套的漏洞环境

    Open source ↗

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2020-17523?
CVE-2020-17523 is a critical vulnerability published on February 3, 2021. Apache Shiro before 1.7.1, when using Apache Shiro with Spring, a specially crafted HTTP request may cause an authentication bypass.
When was CVE-2020-17523 disclosed?
CVE-2020-17523 was first published in the National Vulnerability Database on February 3, 2021, with the most recent update on November 21, 2024. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2020-17523 actively exploited?
CVE-2020-17523 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 99.7% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2020-17523?
CVE-2020-17523 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2020-17523?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2020-17523, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2020-17523

Explore →

Is Your Infrastructure Affected by CVE-2020-17523?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.

Start Free Scan →Browse All CVEs