BlackTreeCVE Intelligence
← Back to the CVE catalogue
Full vulnerability report · 2026
CVE-2026-26927High confidence

URL (HTTP Origin) call location spoofing in Szafir SDK Web

Krajowa Izba Rozliczeniowa · Szafir SDK Web

5.1MediumCVSS 4.0
Recommended action
Scheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityMediumOperational priority:Medium, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • EPSS is 0.27% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict the affected network interface to trusted sources where business-safe.
  • Monitor vendor guidance and exploitation sources for a material change.

Verification

  1. Confirm that the asset runs Krajowa Izba Rozliczeniowa Szafir SDK Web and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: As exposure requiresRemediation target: Within 365 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-18228

No EUVD known-exploited evidence

ENISA has published the identifier mapping but no EUVD description has been stored yet.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
Not supplied in the stored EUVD record
Advisory evidence
No linked advisory details stored yet
Recommended actionScheduled

Medium technical severity with no CISA KEV confirmation; remediate through the normal risk-based patch cycle unless local exposure raises the priority.

Patch available
01

What, why and how

Szafir SDK Web is a browser plug-in that can run SzafirHost application which download the necessary files when launched. In Szafir SDK Web it is possible to change the URL (HTTP Origin) of the application call location. An unauthenticated attacker can craft a website that is able to launch SzafirHost application with arbitrary arguments via Szafir SDK Web browser addon. No validation will be performed to check whether the address specified in `document_base_url` parameter is in any way related to the actual address of the calling web application. The URL address specified in `document_base_url` parameter is then shown in the application confirmation prompt. When a victim confirms the execution of the application, it will be called in the context of attacker's website URL and might download additional files and libraries from that website. When victim accepts the application execution for the URL showed in the confirmation prompt with the "remember" option before, the prompt won't be shown and the application will be called in the context of URL provided by the attacker without any interaction. This issue was fixed in version 0.0.17.4.

What

Szafir SDK Web is a browser plug-in that can run SzafirHost application which download the necessary files when launched. In Szafir SDK Web it is possible to change the URL (HTTP Origin) of the application call location. An unauthenticated attacker can craft a website that is able to launch SzafirHost application with arbitrary arguments via Szafir SDK Web browser addon. No validation will be performed to check whether the address specified in `document_base_url` parameter is in any way related to the actual address of the calling web application. The URL address specified in `document_base_url` parameter is then shown in the application confirmation prompt. When a victim confirms the execution of the application, it will be called in the context of attacker's website URL and might download additional files and libraries from that website. When victim accepts the application execution for the URL showed in the confirmation prompt with the "remember" option before, the prompt won't be shown and the application will be called in the context of URL provided by the attacker without any interaction. This issue was fixed in version 0.0.17.4.

Why

The product has two different sources of the same data or information, but it uses the source that has less support for verification, is less trusted, or is less resistant to attack.

How

An attacker operating through a network path may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

Szafir SDK Web is a browser plug-in that can run SzafirHost application which download the necessary files when launched. In Szafir SDK Web it is possible to change the URL (HTTP Origin) of the application call location. An unauthenticated attacker can craft a website that is able to launch SzafirHost application with arbitrary arguments via Szafir SDK Web browser addon. No validation will be performed to check whether the address specified in `document_base_url` parameter is in any way related to the actual address of the calling web application. The URL address specified in `document_base_url` parameter is then shown in the application confirmation prompt. When a victim confirms the execution of the application, it will be called in the context of attacker's website URL and might download additional files and libraries from that website. When victim accepts the application execution for the URL showed in the confirmation prompt with the "remember" option before, the prompt won't be shown and the application will be called in the context of URL provided by the attacker without any interaction. This issue was fixed in version 0.0.17.4.

Why

The product has two different sources of the same data or information, but it uses the source that has less support for verification, is less trusted, or is less resistant to attack.

How

An attacker operating through a network path may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
None recorded

No exploit-tagged reference or CISA SSVC proof-of-concept state is currently recorded. Research may still exist outside the structured feeds.

Likely attack path
a network path → Use of Less Trusted Source → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Network
Privileges required
None: unauthenticated exploitation is possible
User interaction
Active interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-348 ↗

CWE-348: Use of Less Trusted Source. The product has two different sources of the same data or information, but it uses the source that has less support for verification, is less trusted, or is less resistant to attack.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N

Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.

AVNetworkAttack vector: The vulnerable component can be reached over a network.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATNoneAttack requirements: No additional deployment or execution condition is required.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIActiveUser interaction: A user must take a deliberate action for exploitation to succeed.VCNoneVulnerable-system confidentiality: No direct loss is represented by this metric.VILowVulnerable-system integrity: A successful attack can cause a limited loss.VANoneVulnerable-system availability: No direct loss is represented by this metric.SCNoneSubsequent-system confidentiality: No direct loss is represented by this metric.SINoneSubsequent-system integrity: No direct loss is represented by this metric.SANoneSubsequent-system availability: No direct loss is represented by this metric.
Post-exploitation / living off the land
No specific living-off-the-land technique is confirmed in the structured sources. Monitor normal administration tools for activity inconsistent with the affected service's baseline.
NetworkUnauthenticatedCWE-348
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

CERT Polska · Polish · CVE-2026-26927CERT Polska w social mediach

CERT Polska otrzymał zgłoszenie o podatnościach w oprogramowaniu Szafir i koordynował proces ujawniania informacji. Podatność CVE-2026-26927 : Szafir SDK Web to wtyczka przeglądarkowa, która uruchamia aplikację SzafirHost. Podczas startu aplikacja pobiera niezbędne do działania pliki. W Szafir SDK Web można zmienić adres URL (HTTP Origin) lokalizacji wywołania aplikacji. Nieuwierzytelniony atakujący może stworzyć stronę internetową, która jest w stanie uruchomić aplikację SzafirHost z dowolnymi argumentami za pośrednictwem wtyczki przeglądarki Szafir SDK Web. Nie jest przeprowadzana żadna walidacja, aby sprawdzić, czy adres określony w parametrze document_base_url ma związek z rzeczywistym adresem wywołującej aplikację domeny. Adres URL określony w parametrze document_base_url jest następnie zawarty w oknie potwierdzenia wyświetlanym przez aplikację. Gdy ofiara potwierdzi uruchomienie aplikacji, zostanie ona wywołana w kontekście adresu URL strony internetowej atakującego i może pobrać dodatkowe pliki i biblioteki z tej strony. Jeśli ofiara wcześniej zaakceptowała uruchomienie aplikacji dla adresu URL wyświetlanego w oknie potwierdzenia z opcją "pamiętaj", okno potwierdzenia nie będzie wyświetlane, a aplikacja zostanie wywołana w kontekście adresu URL podanego przez atakującego bez żadnej interakcji ze strony ofiary. Problem został naprawiony w wersji 0.0.17.4. Podatność CVE-2026-26928 : SzafirHost pobiera niezbędne pliki w kontekście wywołującej strony internetowej. Podczas wywoływania, SzafirHost aktualizuje swoją bibliotekę dynamiczną. Pliki JAR są poprawnie weryfikowane na podstawie listy zaufanych skrótów plików, a jeśli plik nie jest na tej liście, zostaje sprawdzone, czy plik został cyfrowo podpisany przez producenta. Aplikacja nie weryfikuje skrótu ani cyfrowego podpisu producenta dla przesyłanych plików DLL, SO, JNILIB lub DYLIB. Atakujący może dostarczyć złośliwy plik, który zostanie zapisany w katalogu /temp użytkownika i wykonany przez aplikację. Problem został naprawiony w wersji 1.1.0.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
Szafir SDK Web: < 0.0.17.4
Fixed
0.0.17.4.
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. If business-safe, reduce exposure to the affected interface and allow only trusted sources until authoritative guidance is available.
04

Evidence and provenance

Published 2 Apr 2026 · Last source change 2 Apr 2026, 14:19 UTC · CWE-348 · Use of Less Trusted Source

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-14
European sourceENISA EUVD · EUVD-2026-18228
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗

No material field changes have been recorded since change tracking began. Routine source refreshes and cosmetic edits are intentionally excluded.

Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-26927 · cve.blacktree.nl