Koha: Improper Neutralization of Directives in Dynamically Evaluated Code
CVE-2026-19780 is a high-severity improper neutralization of directives in dynamically evaluated code vulnerability in Koha, with a CVSS 3.0 base score of 8.8 out of 10. It can be exploited remotely over the network by an attacker with a low-privileged account, without any action from a user. Affected Koha versions: 25.12.00. The record does not name a fixed version, so check the vendor advisory. There is no confirmed exploitation so far. EPSS estimates a 1.03% chance of exploitation within 30 days, higher than 64% of scored CVEs.
High severity with no evidence of exploitation so far.
What to do
- Check which version of Koha you run against the affected versions below, and install the vendor's latest release.
Affected products and versions
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.
- Privileges required
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Scope
- UnchangedImpact stays within the vulnerable component.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- HighData or code can be modified at will.
- Availability
- HighThe component can be taken down completely.
Vector: CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. Scored by CNA (trendmicro.com).
Official description
Koha Eval Code Injection Remote Code Execution Vulnerability. This vulnerability allows remote attackers to execute arbitrary code on affected installations of Koha. Authentication is required to exploit this vulnerability. The specific flaw exists within the web service, which listens on TCP port 8081 by default. The issue results from the lack of proper validation of a user-supplied string before passing it to the eval function. An attacker can leverage this vulnerability to execute code in the context of the service account. Was ZDI-CAN-29165.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Directives in Dynamically Evaluated Code
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes code syntax before using the input in a dynamic evaluation call (e.g. eval).
How developers prevent this class of flaw
- If possible, refactor your code so that it does not need to use eval() at all.
- For Python programs, it is frequently encouraged to use the ast.literal_eval() function instead of eval, since it is intentionally designed to avoid executing code. However, an adversary could still cause excessive memory or stack consumption via deeply nested structures, so the python documentation discourages use of ast.literal_eval() on untrusted data.
More Improper Neutralization of Directives in Dynamically Evaluated Code vulnerabilities (CWE-95)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: total).
- Record last changed materially (score, affected products, status or references).
References
Other references
Other vulnerabilities in Koha
- 10.0 Critical severity
- 9.6 Critical severity
- 8.0 High severity
Recent Improper Neutralization of Directives in Dynamically Evaluated Code vulnerabilities
- 9.9 Critical severity
- 8.8 High severity
- 9.8 Critical severity
- 7.2 High severity
- 8.6 High severity
- 9.9 Critical severity
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