CVE-2020-1957Shiro Authentication Bypass
Improper Authentication in Apache Shiro
Published May 7, 2021 · Updated Oct 20, 2026 · Also known as DEBIAN-CVE-2020-1957, DLA-2181-1, GHSA-26gr-cvq3-qxgf, UBUNTU-CVE-2020-1957
Key Facts
Patch immediately- CVE-2020-1957 is a critical-severity vulnerability (CVSS 9.8 v3.1) affecting Shiro (Apache), Debian Linux, org.apache.shiro:shiro-core (maven).
- It is exploited in the wild, listed in Industry KEV feed since Apr 12, 2021. No public exploit code is known.
- EPSS estimates a 23% probability of exploitation in the next 30 days.
- Fixed versions are available, including Shiro 1.5.2, Shiro 1.2.3-1+deb8u1, Shiro 1.3.2-1+deb9u1.
- Brandefense priority: patch immediately, because it is listed as exploited in the wild.
Scores
CVSS v3.1
9.8
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS (30-day exploit likelihood)
23%
Higher than 97.7% of all scored CVEs
Exploit maturity
Exploited (KEV)
ATLAS score
55/100
Publication score, see How it works
Exploitation Verdict
KEV listed
Apr 12, 2021
-25 days after publication
Federal due date
None
No federal due date
Ransomware use
Not reported
Attributed actors
None named
Exploit & Defence Guidance
Exploit maturity
Exploited (KEV)
Public exploit code
0
Proof-of-concept links
In-the-wild evidence
1
Reports of active use
Advisories And Exploit References
- advisoryhttps://nvd.nist.gov/vuln/detail/CVE-2020-1957
- advisoryhttps://security-tracker.debian.org/tracker/CVE-2020-1957
- advisoryhttps://ubuntu.com/security/CVE-2020-1957
- advisoryhttps://www.cve.org/CVERecord?id=CVE-2020-1957
- advisoryGHSA advisory
- advisoryhttps://github.com/apache/shiro/pull/203#issuecomment-605442534
Description
Apache Shiro before 1.5.2, when using Apache Shiro with Spring dynamic controllers, a specially crafted request may cause an authentication bypass.
Known-Exploited Catalog Listings
| Catalog | Added | Remediation due | Ransomware use |
|---|---|---|---|
| Industry KEV feed | Apr 12, 2021 | n/a | Not reported |
Affected Products
17 affected entries in total| Product | Affected versions | Fixed in |
|---|---|---|
| ShiroApache | >= Apache Shiro to 1.5.2 | 1.5.2 |
| Debian LinuxDebian | 8.0 | n/a |
| org.apache.shiro:shiro-coremaven | See advisory | 1.5.2 |
Patched Releases
Shiro
1.5.2, 1.2.3-1+deb8u1, 1.3.2-1+deb9u1, 1.3.2-3~18.04.1, 1.3.2-4+deb11u1, 1.3.2-4ubuntu0.1, 1.3.2-5
org.apache.shiro:shiro-core
1.5.2
Timeline
Added to Industry KEV feed
Apr 12, 2021
Publicly disclosed
May 7, 2021
Last updated
Oct 20, 2026
Weakness Type
- CWE-287 Improper Authentication
References
- advisorynvd.nist.gov · CVE-2020-1957
- advisorysecurity-tracker.debian.org · CVE-2020-1957
- advisoryubuntu.com · CVE-2020-1957
- advisorycve.org · CVERecord
- advisoryGHSA advisory
FAQ
Common Questions.
Apache Shiro before 1.5.2, when using Apache Shiro with Spring dynamic controllers, a specially crafted request may cause an authentication bypass.
Affected: Shiro (Apache) versions >= Apache Shiro to 1.5.2; Debian Linux versions 8.0; org.apache.shiro:shiro-core (maven). The full list is in the CVE brief.
It is exploited in the wild, listed in Industry KEV feed since Apr 12, 2021.
No, it is not currently listed in the CISA Known Exploited Vulnerabilities catalog.
No public exploit code is known.
Fixed versions are available, including Shiro 1.5.2, Shiro 1.2.3-1+deb8u1, Shiro 1.3.2-1+deb9u1.
Brandefense priority: patch immediately, because it is listed as exploited in the wild.
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