MISP: Improper Neutralization of Escape, Meta, or Control Sequences
CVE-2026-90895 is a high-severity improper neutralization of escape, meta, or control sequences vulnerability in MISP, with a CVSS 4.0 base score of 8.4 out of 10. It can be exploited with local access to the system by an attacker with a low-privileged account, without any action from a user. The record lists version 2.5.46 as the first without the flaw, so updating MISP to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.15% chance of exploitation within 30 days, which is low compared with other CVEs.
High severity with no evidence of exploitation so far.
What to do
- Update MISP to 2.5.46 or a later version.
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
- LocalThe attacker needs local access or must trick a user into running something.
- 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
- LowA basic user account is enough.
- User interaction
- NoneNo action by a victim is required.
- Confidentiality (vulnerable system)
- HighSerious 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:L/AC:L/AT:N/PR:L/UI:N/VC:H/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.
Official description
Affected versions of MISP’s interactive CLI shell implement access control independently from the normal web application, causing several authorization inconsistencies. The patch shows that CLI access could differ from the web application in multiple security-sensitive areas: - feed listings did not enforce the same lookup_visible restrictions for non-host-organisation users; - feed detail access did not enforce the same host-organisation/site-admin authorization as FeedsController::view(); - Feed.headers, which can contain HTTP authorization credentials, could be exposed instead of being hidden or masked; - server synchronization authkey values were not explicitly hidden from CLI detail output; - sharing-group detail access did not consistently use SharingGroup::checkIfAuthorised(); - the use command could establish context for a record without first proving that the user was authorized to view that record The commit additionally hardens pagination and terminal rendering, including neutralization of terminal control sequences found in database-backed values. Those are important hardening changes, but the main vulnerability is the CLI authorization/data-disclosure mismatch. Version affected: ≤2.5.45
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Improper Neutralization of Escape, Meta, or Control Sequences
The product receives input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could be interpreted as escape, meta, or control character sequences when they are sent to a downstream component.
How developers prevent this class of flaw
- Developers should anticipate that escape, meta and control characters/sequences will be injected/removed/manipulated in the input vectors of their product. Use an appropriate combination of denylists and allowlists to ensure only valid, expected and appropriate input is processed by the system.
- While it is risky to use dynamically-generated query strings, code, or commands that mix control and data together, sometimes it may be unavoidable. Properly quote arguments and escape any special characters within those arguments. The most conservative approach is to escape or filter all characters that do not pass an extremely strict allowlist (such as everything that is not alphanumeric or white space). If some special characters are still needed, such as white space, wrap each argument in quotes after the escaping/filtering step. Be careful of argument injection (CWE-88).
- Inputs should be decoded and canonicalized to the application's current internal representation before being validated (CWE-180). Make sure that the application does not decode the same input twice (CWE-174). Such errors could be used to bypass allowlist validation schemes by introducing dangerous inputs after they have been checked.
More Improper Neutralization of Escape, Meta, or Control Sequences vulnerabilities (CWE-150)
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
Patches and release notes
Other vulnerabilities in MISP
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
- 7.1 High severity
Recent Improper Neutralization of Escape, Meta, or Control Sequences vulnerabilities
- 8.8 High severity
- 7.1 High severity
- 7.5 High severity
- 7.8 High severity
- 7.8 High severity
- 9.0 Critical severity
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