GHSA-4hmj-39m8-jwc7 CVE-2026-35651
OpenClaw has ACP CLI approval prompt ANSI escape sequence injection
Medium
npm
- Severity
- 0.0 / 10
- Medium · CVSS 4.0
- Exploit chance (EPSS)
- 0.26%
- Chance of exploitation in the next 30 days. Higher than 17.82% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-116 Improper Encoding or Escaping of Output
- CWE-150 Improper Neutralization of Escape, Meta, or Control Sequences
- Fix
2026.3.28- Upgrade openclaw to this version or later
Description
Summary
ACP CLI approval prompt ANSI escape sequence injection
Affected Packages / Versions
- Package:
openclaw - Affected versions:
>= 2026.2.13, <= 2026.3.24 - First patched version:
2026.3.25 - Latest published npm version at verification time:
2026.3.24
Details
ACP tool titles could previously carry ANSI control sequences into approval prompts and permission logs, letting untrusted tool metadata spoof terminal output. Commit 464e2c10a5edceb380d815adb6ff56e1a4c50f60 sanitizes tool titles at the source and broadens ANSI stripping to full CSI sequences.
Verified vulnerable on tag v2026.3.24 and fixed on main by commit 464e2c10a5edceb380d815adb6ff56e1a4c50f60.
Fix Commit(s)
464e2c10a5edceb380d815adb6ff56e1a4c50f60
Affected versions
npm
| Package | Vulnerable | Fixed in |
|---|---|---|
| openclaw | >= 2026.2.13, < 2026.3.28 |
2026.3.28 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
openclaw npm → 2026.3.28
- npm
npm install openclaw@2026.3.28- yarn
yarn add openclaw@2026.3.28- pnpm
pnpm add openclaw@2026.3.28
Severity breakdown
CVSS 4.0 0.0
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N
- Attack vector
- Network
- Attack complexity
- Low
- Attack requirements
- None
- Privileges required
- None
- User interaction
- Passive
- Confidentiality (vulnerable system)
- None
- Integrity (vulnerable system)
- Low
- Availability (vulnerable system)
- None
- Confidentiality (subsequent systems)
- None
- Integrity (subsequent systems)
- None
- Availability (subsequent systems)
- None
CVSS 3.1 4.3
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:L/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- None
- Integrity
- Low
- Availability
- None
Weakness
CWE-116: Improper Encoding or Escaping of Output
The product prepares a structured message for communication with another component, but encoding or escaping of the data is either missing or done incorrectly. As a result, the intended structure of the message is not preserved.
How to prevent it
- Architecture and Design: Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid. For example, consider using the ESAPI Encoding control [REF-45] or a similar tool, library, or framework. These will help the programmer encode outputs in a manner less prone to error. Alternately, use built-in functions, but consider using wrappers in case those functions are discovered to have a vulnerability.
- Architecture and Design: If available, use structured mechanisms that automatically enforce the separation between data and code. These mechanisms may be able to provide the relevant quoting, encoding, and validation automatically, instead of relying on the developer to provide this capability at every point where output is generated. For example, stored procedures can enforce database query structure and reduce the likelihood of SQL injection.
- Architecture and Design, Implementation: Understand the context in which your data will be used and the encoding that will be expected. This is especially important when transmitting data between different components, or when generating outputs that can contain multiple encodings at the same time, such as web pages or multi-part mail messages. Study all expected communication protocols and data representations to determine the required encoding strategies.
- Architecture and Design: In some cases, input validation may be an important strategy when output encoding is not a complete solution. For example, you may be providing the same output that will be processed by multiple consumers that use different encodings or representations. In other cases, you may be required to allow user-supplied input to contain control information, such as limited HTML tags that support formatting in a wiki or bulletin board. When this type of requirement must be met, use an extremely strict allowlist to limit which control sequences can be used. Verify that the resulting syntactic structure is what you expect. Use your normal encoding methods for the remainder of the input.
- Architecture and Design: Use input validation as a defense-in-depth measure to reduce the likelihood of output encoding errors (see CWE-20).
- Requirements: Fully specify which encodings are required by components that will be communicating with each other.
- Implementation: When exchanging data between components, ensure that both components are using the same character encoding. Ensure that the proper encoding is applied at each interface. Explicitly set the encoding you are using whenever the protocol allows you to do so.
CWE-150: 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 to prevent it
- 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.
- Implementation: Assume all input is malicious. Use an "accept known good" input validation strategy, i.e., use a list of acceptable inputs that strictly conform to specifications. Reject any input that does not strictly conform to specifications, or transform it into something that does. When performing input validation, consider all potentially relevant properties, including length, type of input, the full range of acceptable values, missing or extra inputs, syntax, consistency across related fields, and conformance to business rules. As an example of business rule logic, "boat" may be syntactically valid because it only contains alphanumeric characters, but it is not valid if the input is only expected to contain colors such as "red" or "blue." Do not rely exclusively on looking for malicious or malformed inputs. This is likely to miss at least one undesirable input, especially if the code's environment changes. This can give attackers enough room to bypass the intended validation. However, denylists can be useful for detecting potential attacks or determining which inputs are so malformed that they should be rejected outright.
- Implementation: 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).
- Implementation: 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.
- Implementation: When using output from an LLM, neutralize or strip escape codes before redirecting output to the terminal or other rendering engine that would process the codes. The neutralization could require that the character be printable and/or allowable whitespace, such as a carriage return or newline. Be deliberate about what to allow.
- Build and Compilation: When using an LLM: during tokenizer training, suppress escape codes from the tokenizer's vocabulary. Depending on context, this could be accomplished by removing the codes from input to the tokenizer, or removing the map from the string to its token ID. It is generally unlikely that this removal would adversely affect the quality or correctness of what is generated, e.g. advice requests for terminal settings to change colors.
References
Advisories
Packages
Other links
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-3x84-qq85-fj65 OpenClaw: Browser CDP discovery could accept blocked WebSocket URLs | High | Also affects openclaw |
| GHSA-9c3v-684m-579c OpenClaw MCP SSE redirects could forward Authorization headers | Medium | Also affects openclaw |
| GHSA-f397-5vjw-v2c2 OpenClaw: Shell inline-command parsing could miss an allowlist check | High | Also affects openclaw |
| GHSA-rx78-29qr-5hq8 OpenClaw: Workspace-derived service PATH could influence trash command selection | High | Also affects openclaw |
| GHSA-ccwh-wwpp-6wg5 OpenClaw: Host environment sanitizer missed two Node.js control variables | High | Also affects openclaw |
| GHSA-985f-72mj-8gf7 OpenClaw: Tool group policy callers could accept unvalidated group IDs | Medium | Also affects openclaw |
| GHSA-9v8j-9c9g-w66c OpenClaw: Bootstrap token replay could widen pending pairing scopes | Medium | Also affects openclaw |
| GHSA-c226-q6fx-6j6c OpenClaw: macOS Swift exec allowlist missed combined POSIX inline flags | Medium | Also affects openclaw |
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