Security readout for executives and security teams
Plain-English summary
OpenProject versions before 16.6.2 allowed attackers to repeatedly try password changes without the usual brute-force protections. If an attacker knows or guesses a valid user ID, they could automate password guessing and take over that account. Business impact depends on the compromised user’s role and permissions inside OpenProject.
Executive priority
Treat as a near-term remediation item for any exposed OpenProject instance. It is not rated critical and has no confirmed active exploitation in the provided sources, but successful abuse can result in account takeover and project data exposure or manipulation.
Technical view
CVE-2026-22603 is a CWE-307 improper restriction of excessive authentication attempts affecting OpenProject before 16.6.2. The unauthenticated password-change flow lacked the brute-force safeguards applied to normal login. CVSS v4.0 is 6.9. Successful guessing can compromise user accounts and may enable additional in-application privilege escalation depending on role.
Likely exposure
Organizations running OpenProject below 16.6.2 are exposed, especially internet-facing deployments or environments where user IDs can be guessed or enumerated. The issue is in OpenProject itself; no other affected products are identified in the provided sources.
Exploitation context
The source bundle does not indicate CISA KEV listing or confirmed active exploitation. Exploitation requires guessing or enumerating a valid user ID and successfully guessing that user’s password through repeated attempts.
Researcher notes
The advisory states the vulnerable password-change endpoint lacked normal login brute-force protections. Public sources identify the fix in 16.6.2 and a related pull request and commit. Evidence is sufficient for affected-version and remediation guidance, but no public exploitation evidence is provided in the bundle.
Mitigation direction
- Upgrade OpenProject to version 16.6.2 or later.
- If upgrade is not possible, apply the vendor-provided patch manually.
- Review vendor advisory and release notes before production rollout.
- Prioritize accounts with elevated OpenProject permissions for password review.
Validation and detection
- Inventory all OpenProject instances and record running versions.
- Confirm affected instances are upgraded to 16.6.2 or later.
- Verify the vendor patch is applied where upgrades are deferred.
- Review authentication-related logs for unusual password-change attempt volume.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-307: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupPrivilege behavior lookup
The CVE wording references privilege impact, so privilege escalation and authorization behavior review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2026-22603 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Medium
- CVSS
- 6.9 (4.0)
- Known Exploited
- No
- Published
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N——Primary CVE scoreVulnerability scoring details
Base CVSS 4.0 score
6.9MediumVector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/opf/openproject/security/advisories/GHSA-93x5-prx9-x239CVE reference · x_refsource_CONFIRM
- https://github.com/opf/openproject/pull/21272CVE reference · x_refsource_MISC
- https://github.com/opf/openproject/commit/2b394b9ba5af1e5d96a64d7d452d4d44598a4c7fCVE reference · x_refsource_MISC
- https://github.com/opf/openproject/releases/tag/v16.6.2CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Restriction of Excessive Authentication Attempts
Improper Restriction of Excessive Authentication Attempts represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.