Visual Studio Code: Inconsistent Interpretation of HTTP Requests
CVE-2026-81356 is a high-severity inconsistent interpretation of HTTP requests vulnerability in Visual Studio Code from Microsoft, with a CVSS 3.1 base score of 8.2 out of 10. It can be exploited remotely over the network by an unauthenticated attacker, but only if a user takes part, for example by opening a link or file. The record lists version 1.136.2 as the first without the flaw, so updating Visual Studio Code to that release or later removes the exposure. There is no confirmed exploitation so far. EPSS estimates a 0.54% 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 Visual Studio Code to 1.136.2 or a later version.
- Read the advisory on msrc.microsoft.com for workarounds and exact fixed builds.
- Until you can update, restrict network access to the affected service so it is not reachable from untrusted networks.
- Because the attack needs a user to take part, warn users about unexpected links and files related to this product until it is patched.
Affected products and versions
| Vendor | Product | Affected versions | Fixed in |
|---|---|---|---|
| Microsoft | Visual Studio Code | 1.0.0 up to, but not including, 1.136.2 | 1.136.2 |
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
- NoneNo account or login is needed.
- User interaction
- RequiredA user must take an action such as opening a file or link.
- Scope
- ChangedThe attack can reach beyond the vulnerable component into other systems.
- Confidentiality
- HighAll data handled by the component can be read.
- Integrity
- LowLimited modification of data is possible.
- Availability
- NoneAvailability is not affected.
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:L/A:N. Scored by CNA (microsoft.com).
Official description
Inconsistent interpretation of http requests ('http request/response smuggling') in Visual Studio Code allows an unauthorized attacker to bypass a security feature over a network.
Source: the CVE record as published by its numbering authority, via NVD and CVE.org.
The underlying weakness: Inconsistent Interpretation of HTTP Requests
The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.
How developers prevent this class of flaw
- Use a web server that employs a strict HTTP parsing procedure, such as Apache.
- Terminate the client session after each request.
More Inconsistent Interpretation of HTTP Requests vulnerabilities (CWE-444)
Timeline
- CVE record published.
- CISA published its SSVC assessment (exploitation: none, automatable: no, technical impact: partial).
- Record last changed materially (score, affected products, status or references).
References
Other vulnerabilities in Visual Studio Code
- 8.3 High severity
- 8.6 High severity
- 8.8 High severity
- 8.8 High severity
- 9.6 Critical severity
- 7.5 High severity
Recent Inconsistent Interpretation of HTTP Requests vulnerabilities
- 8.3 High severity
- 8.3 High severity
- 8.3 High severity
- 8.3 High severity
- 7.5 High severity
- 9.1 Critical severity
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