CVE-2026-44598 | Apache Shiro Jakarta EE module: Open redirect and SSRF (requires valid credentials)

With valid login credentials, URL Redirection to Untrusted Site ('Open Redirect'), Server-Side Request Forgery (SSRF) vulnerability in Apache Shiro. This issue affects Apache Shiro from 2.0-alpha to 2.1.0, and 3.0.0-alpha-1, only when using shiro-jakarta-ee integration module. Users are recommended to upgrade to version 2.1.1, or 3.0.0-alpha-2 or later, which fixes the issue by encrypting the cookie. After successful login, Jakarta EE integration module uses shiroSavedRequest cookie to redirect to a particular web page after login. This cookie was not validated, and can be forged to send a HTTP GET request from the server itself to an arbitrary URL from the cookie.

Published: 2026-05-25 Last update: 2026-05-28 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-44598 is rated Low Risk (31.1/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.12%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-44598

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-29 0.04% 0.12% +0.08%
2 2026-05-26 0.04%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-44598

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.1 4.0 MEDIUM
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:P/VC:L/VI:N/VA:N/SC:L/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:N/AU:Y/R:A/V:D/RE:L/U:Green Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network.
Attack complexity (AC:L)
Exploitation conditions are straightforward and stable.
Attack requirements (AT:N)
No additional preconditions are required beyond normal reachability.
Privileges required (PR:L)
Low privileges are required.
User interaction (UI:P)
A user has to participate (for example click/open/approve).
Vulnerable system confidentiality impact (VC:L)
Limited confidentiality impact on the vulnerable system.
Vulnerable system integrity impact (VI:N)
No integrity impact on the vulnerable system.
Vulnerable system availability impact (VA:N)
No availability impact on the vulnerable system.
Subsequent system confidentiality impact (SC:L)
Limited confidentiality impact on subsequent systems.
Subsequent system integrity impact (SI:N)
No integrity impact on subsequent systems.
Subsequent system availability impact (SA:N)
No availability impact on subsequent systems.
Exploit maturity (threat) (E:X)
Not defined: no reliable threat intelligence; scoring assumes the worst case (equivalent to Attacked).
Confidentiality requirement (CR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Integrity requirement (IR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Availability requirement (AR:X)
Not defined: insufficient information; scoring treats this like High (worst case).
Modified attack vector (MAV:X)
Not defined: scoring uses the Base Attack Vector (AV).
Modified attack complexity (MAC:X)
Not defined: scoring uses the Base Attack Complexity (AC).
Modified attack requirements (MAT:X)
Not defined: scoring uses the Base Attack Requirements (AT).
Modified privileges required (MPR:X)
Not defined: scoring uses the Base Privileges Required (PR).
Modified user interaction (MUI:X)
Not defined: scoring uses the Base User Interaction (UI).
Modified vulnerable system confidentiality impact (MVC:X)
Not defined: scoring uses the Base VC metric.
Modified vulnerable system integrity impact (MVI:X)
Not defined: scoring uses the Base VI metric.
Modified vulnerable system availability impact (MVA:X)
Not defined: scoring uses the Base VA metric.
Modified subsequent system confidentiality impact (MSC:X)
Not defined: scoring uses the Base SC metric.
Modified subsequent system integrity impact (MSI:X)
Not defined: scoring uses the Base SI metric.
Modified subsequent system availability impact (MSA:X)
Not defined: scoring uses the Base SA metric.
Safety (supplemental) (S:N)
Negligible: impact meets the IEC 61508 negligible safety consequence category.
Automatable (supplemental) (AU:Y)
Yes: all four kill-chain steps (reconnaissance, weaponization, delivery, exploitation) can be automated.
Recovery (supplemental) (R:A)
Automatic: services recover on their own after an attack.
Value density (supplemental) (V:D)
Diffuse: a single exploit event controls relatively limited resources (e.g., one client).
Vulnerability response effort (supplemental) (RE:L)
Low/trivial response effort (documentation, simple configuration, low-touch guidance).
Provider urgency (supplemental) (U:GREEN)
Green: provider rates reduced urgency.
[email protected]
5.4 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:C)
Breaking this can reach past the original component and bite other resources—bigger blast radius.
Confidentiality (C:L)
Some sensitive info could get out, but not a total data dump.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
2.3 2.7 [email protected]

Weakness enumeration for CVE-2026-44598

GitHub Security Advisory for CVE-2026-44598

GHSA-wpqm-4gwx-w843 · Severity: medium — With valid login credentials, URL Redirection to Untrusted Site ('Open Redirect'), Server-Side...

OS Trackers for CVE-2026-44598

vendor priority summary link
debian unimportant CVE-2026-44598 unimportant priority: Debian including 1 source packages (shiro), 4 status rows across 4 suites (bookworm, bullseye, sid, trixie): resolved 4. https://security-tracker.debian.org/tracker/CVE-2026-44598
ubuntu medium CVE-2026-44598 medium priority: Ubuntu including 1 source packages (shiro), 7 status rows across 7 suites (bionic, focal, jammy, noble, questing, resolute, upstream): needs-triage 6, not-affected 1. https://ubuntu.com/security/CVE-2026-44598

Affected software / configurations for CVE-2026-44598

Vendor Product Version Raw CPE
apache shiro >= 2.0.0, < 2.1.1 cpe:2.3:a:apache:shiro:*:*:*:*:*:*:*:*
apache shiro 3.0.0 cpe:2.3:a:apache:shiro:3.0.0:alpha1:*:*:*:*:*:*

References for CVE-2026-44598

cvelogic Threat Intelligence