CyberSecBulletin
CVE-2026-26928NVD status: Deferred

SzafirHost: Improper Validation of Integrity Check Value

Published Updated By the CyberSecBulletin desk

CVE-2026-26928 is a high-severity improper validation of integrity check value vulnerability in SzafirHost from Krajowa Izba Rozliczeniowa, with a CVSS 4.0 base score of 8.7 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, without any action from a user. The record lists version 1.1.0 as the first without the flaw, so updating SzafirHost to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.2% chance of exploitation within 30 days, which is low compared with other CVEs.

Next patch cycle

High severity with no evidence of exploitation so far.

What to do

  1. Update SzafirHost to 1.1.0 or a later version.
  2. Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.

Affected products and versions

VendorProductAffected versionsFixed in
Krajowa Izba RozliczeniowaSzafirHostbefore 1.1.01.1.0

Version data comes from the organisation that assigned the CVE. Confirm against the vendor advisory before deciding you are unaffected.

How the severity score breaks down

Attack vector
NetworkCan be exploited remotely over a network, including the internet.
Attack complexity
LowNo special conditions are needed; the attack works reliably.
Attack requirements
NoneThe attack does not depend on a particular deployment or configuration.
Privileges required
NoneNo account or login is needed.
User interaction
NoneNo action by a victim is required.
Confidentiality (vulnerable system)
NoneNo loss of confidentiality on the vulnerable system.
Integrity (vulnerable system)
HighSerious loss of integrity on the vulnerable system.
Availability (vulnerable system)
NoneNo loss of availability on the vulnerable system.
Confidentiality (other systems)
NoneNo loss of confidentiality on systems beyond the vulnerable one.
Integrity (other systems)
NoneNo loss of integrity on systems beyond the vulnerable one.
Availability (other systems)
NoneNo loss of availability on systems beyond the vulnerable one.

Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/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:X/AU:X/R:X/V:X/RE:X/U:X. Scored by CNA (cert.pl).

Official description

SzafirHost downloads necessary files in the context of the initiating web page. When called, SzafirHost updates its dynamic library. JAR files are correctly verified based on a list of trusted file hashes, and if a file was not on that list, it was checked to see if it had been digitally signed by the vendor. The application doesn't verify hash or vendor's digital signature of uploaded DLL, SO, JNILIB or DYLIB file. The attacker can provide malicious file which will be saved in users /temp folder and executed by the application. This issue was fixed in version 1.1.0.

Source: the CVE record as published by its numbering authority, via NVD and CVE.org.

The underlying weakness: Improper Validation of Integrity Check Value

The product does not validate or incorrectly validates the integrity check values or checksums of a message.

How developers prevent this class of flaw

  • The protocol specification describes the algorithm used for calculating the checksum. It is then a matter of implementing the calculation and verifying that the calculated checksum and the received checksum match.

More Improper Validation of Integrity Check Value vulnerabilities (CWE-354)

Timeline

  1. CVE record published.
  2. CISA published its SSVC assessment (exploitation: none, automatable: yes, technical impact: partial).
  3. Record last changed materially (score, affected products, status or references).

References

Other vulnerabilities in SzafirHost

All SzafirHost vulnerabilities

Recent Improper Validation of Integrity Check Value vulnerabilities

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