CVE-2026-34443 — FreeScout: SSRF protection bypass via broken CIDR check in checkIpByMask()
FreeScout is a free help desk and shared inbox built with PHP's Laravel framework. Prior to version 1.8.211, checkIpByMask() in app/Misc/Helper.php checks whether the input IP contains a / character. Plain IP addresses never contain /, so the function always returns false without checking any CIDR ranges. The entire 10.0.0.0/8 and 172.16.0.0/12 private ranges are unprotected. This issue has been patched in version 1.8.211.
Who exploits it and how urgent it is
A 0–100 score combining confirmed exploitation, ransomware and APT use, public exploits, EPSS and severity.
How the score was calculated
- EPSS 0.4% (30-day exploitation probability)+5
- Technical severity (medium)+3
- Automatable exploitation (SSVC)+3
The score orders the patch queue; it does not replace your asset context (internet exposure, criticality, compensating controls).
Triage
Is it exploited, how likely is exploitation, what does it touch, and how severe do the sources call it.
CISA SSVC assessment CISA
Three decision points CISA publishes for the CVEs it assesses (SSVC 2.0.3). A stakeholder decision, not a severity score.
Remediation
Fixes and mitigations documented by the sources — linked to the original advisory.
- Documented patch — github.com (NIST National Vulnerability Database)
First 24 hours
Ordered from the record’s own fields — exposure first, because you cannot patch what you have not found. A rule-generated starting point.
- Identify exposed assets running the affected vendor/product/version combinations (Freescout Freescout, Freescout-help-desk Freescout).
- The attack is network-based and needs no privileges: restrict exposure (ACLs, VPN, WAF) until patched.
- Apply the fixed version or the patch documented under Remediation.
- Search available logs for exploit probes matching the vulnerability class (ssrf), errors and authentication anomalies.
Affected scope
Vendor, product and versions as the sources word them.
| Vendor | Product | Versions | Status | Source |
|---|---|---|---|---|
| Freescout | Freescout | < 1.8.211 | Vulnerable | NIST National Vulnerability Database |
| Freescout-help-desk | Freescout | version < 1.8.211 | Vulnerable | CVE Program (cve.org) e CISA ADP |
Attack characteristics
The CVSS vector, decoded. It describes the attack, not your exposure to it.
Every base score collected
Sources score independently and may disagree; each row says who scored it and under which version.
| Score | Version | Severity | Expl. | Impact | Scored by |
|---|---|---|---|---|---|
| 6.9 | CVSS 4.0 | Medium | — | — | security-advisories@github.com via NIST National Vulnerability Database |
| 6.9 | CVSS 4.0 | Medium | — | — | GitHub_M via CVE Program (cve.org) e CISA ADP |
| 5.3 | CVSS 3.1 | Medium | 3.9 | 1.4 | nvd@nist.gov via NIST National Vulnerability Database |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N (score shown at the top: nvd@nist.gov) Weakness MITRE
Weakness class according to MITRE’s CWE catalog.
EPSS over time FIRST
Oct 13, 2026 → Oct 14, 2026 · 2 reading(s) · max 0.40%
Detection
Read off the CVSS vector and the weakness class. Starting points, not tested rules.
- Prioritize edge telemetry for the network-reachable component (proxy, WAF, IDS/IPS).
- Monitor outbound requests from the server to internal IPs and cloud metadata endpoints.
Timeline
What happened to this CVE, newest first.
- 2026
- Affected products added · freescout-help-desk/freescout
- SSVC assessment updated
- Record published
- Fix documented
- CVSS changed · 5.3
- Source status changed · → Analyzed
- Record created in this database
- CVE published
Source activity
Repeated readings are counted rather than listed.
- 1× Official description updated · Oct 13, 2026 – Oct 13, 2026
References
3 on the record
Elsewhere on this site
Related CVEs (same products)
- Medium CVE-2026-107393 FreeScout: Stored HTML Injection in Administrator Alert Emails via Spoofed CF-Connecting-IP Header 7d
- Medium CVE-2026-53596 FreeScout has unrestricted file upload without rate limiting that leads to resource exhaustion (DoS) Jul 20, 2026
- Medium CVE-2026-53594 FreeScout has Arbitrary File Read in App Logs Viewer via Forged Encrypted Path Jul 20, 2026
- Critical CVE-2026-53595 FreeScout vulnerable to anonymous account takeover via /user-setup empty invite_hash on MySQL Jul 20, 2026
- Medium CVE-2026-53592 FreeScout vulnerable to prototype pollution in getQueryParam Jul 20, 2026
- High CVE-2026-53591 FreeScout Vulnerable to Unauthenticated Conversation Thread Injection via HMAC Length Bypass in FetchEmails Jul 20, 2026
Not in any source we poll
Listed rather than left blank: an empty field and an unmeasured one look identical on screen, and only one is a reason to look elsewhere.
- No confirmed IOCs, IP addresses, domains, file hashes, or malware artifacts supplied.
- No organization-specific asset inventory, compensating-control status, or patch deployment evidence supplied.
- No exploit packet captures, log samples, or incident case IDs supplied.
Answered from this record
Text assembled only from the fields above — no additional claims.
What should defenders know first?
CVE-2026-34443 is "FreeScout: SSRF protection bypass via broken CIDR check in checkIpByMask()", rated Medium. It affects Freescout (Freescout); versions are in the scope table. It is not in CISA KEV, which does not rule out exploitation. CVSS 5.3 describes technical severity. EPSS 0.40% estimates the probability of exploitation in 30 days; neither replaces your asset context. First verify whether exposed or business-critical assets run the affected versions, apply vendor fixes or mitigations, and preserve logs for review.
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