Advisory details:
github_osv / GHSA-cxpw-2g23-2vgw
| Advisory ID | github_osv/GHSA-cxpw-2g23-2vgw |
| Aliases |
CVE-2026-27576
|
| Summary | OpenClaw: ACP prompt-size checks missing in local stdio bridge could reduce responsiveness with very large inputs ## Vulnerability The ACP bridge accepted very large prompt text blocks and could assemble oversized prompt payloads before forwarding them to `chat.send`. Because ACP runs over local stdio, this mainly affects local ACP clients (for example IDE integrations) that send unusually large inputs. ## Affected Packages / Versions - Package: `openclaw` (npm) - Affected versions: `<= 2026.2.17` - Patched version: `2026.2.18` (planned next release) ## Impact - Local ACP sessions may become less responsive when very large prompts are submitted - Larger-than-expected model usage/cost when oversized text is forwarded - No privilege escalation and no direct remote attack path in the default ACP model ## Affected Components - `src/acp/event-mapper.ts` - `src/acp/translator.ts` ## Remediation - Enforce a 2 MiB prompt-text limit before concatenation - Count inter-block newline separator bytes during pre-concatenation size checks - Keep final outbound message-size validation before `chat.send` - Avoid stale active-run session state when oversized prompts are rejected - Add regression tests for oversize rejection and active-run cleanup ## Fix Commit(s) - `732e53151e8fbdfc0501182ddb0e900878bdc1e3` - `ebcf19746f5c500a41817e03abecadea8655654a` - `63e39d7f57ac4ad4a5e38d17e7394ae7c4dd0b9c` Thanks @aether-ai-agent for reporting. |
| Status | Published |
| Exploitability | 0.5 |
| Weighted Severity | 4.3 |
| Risk | 2.1 |
| Affected and Fixed Packages | Package Details |
| Introduced and Fixed Package Commit Patches | Package Commit Patches Details |
| System | Score | Found at |
|---|---|---|
| cvssv4 | 4.8 | https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/02/GHSA-cxpw-2g23-2vgw/GHSA-cxpw-2g23-2vgw.json |
| generic_textual | MODERATE |
No EPSS data available for this advisory.
| Patch URL | |
|---|---|
| There are no known patches. | |
| Attack Vector (AV) | Attack Complexity (AC) | Attack Requirements (AT) | Privileges Required (PR) | User Interaction (UI) | Vulnerable System Impact Confidentiality (VC) | Vulnerable System Impact Integrity (VI) | Vulnerable System Impact Availability (VA) | Subsequent System Impact Confidentiality (SC) | Subsequent System Impact Integrity (SI) | Subsequent System Impact Availability (SA) |
|---|---|---|---|---|---|---|---|---|---|---|
network adjacent local physical |
low high |
none present |
none low high |
none passive active |
high low none |
high low none |
high low none |
high low none |
high low none |
high low none |
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-02-24T18:11:17Z/
Decision: Track
Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/27xxx/CVE-2026-27576.json
Source Advisory: vulnrichment/CVE-2026-27576
[{'Exploitation': 'none'},
{'Automatable': 'no'},
{'Technical Impact': 'partial'},
{'Mission Prevalence': 'minimal'},
{'Public Well-being Impact': 'material'},
{'Mission & Well-being': 'medium'}]