# Auto-Reseeding HMAC-DRBG could panic for some output lengths Advisory record · `RUSTSEC-2026-0329` - **Identifiers:** `RUSTSEC-2026-0329` - **State:** Confirmed - **Severity:** CVSS 4.0, no score published - **Critical:** No - **Published:** 3 Aug 2026 - **Updated:** 7 Oct 2026 - **Reviewed by a person:** No Published by OSV at 3 Aug 2026, 12:00 UTC. agentprime has not analysed this yet, so whether it affects any app is not known. ## Affected packages - `libcrux-hmac-drbg` (crates.io): affected `>=0.0.0-0, <0.0.2`; fixed in `0.0.2` ## Machine-written summary Summary written by Claude Haiku from the source advisory. Not reviewed by a person. > The libcrux-hmac-drbg package, versions before 0.0.2, has a bug in its auto-reseeding HMAC-DRBG where a call to fill random bytes panics when the requested non-zero output length is an exact multiple of 65,536 bytes. Requests with other lengths are not affected. Upgrade to libcrux-hmac-drbg version 0.0.2, which fixes the issue. Written 3 Nov 2026. ## Not analysed yet We haven’t published our analysis of this Advisory yet. Once a person has reviewed it, this page will say what’s vulnerable, what has to be true for your app to be affected, and how to check. ## Severity and exploitation - Score not published, CVSS 4.0: `CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`, from OSV - **CISA KEV:** Not listed. - **EPSS:** No score. ## Timeline - 31 Oct 2026, 14:24 UTC: First seen by agentprime - 31 Oct 2026, 14:24 UTC: [Confirmed by OSV](https://osv.dev/vulnerability/RUSTSEC-2026-0329) ## Sources - [OSV: RUSTSEC-2026-0329](https://osv.dev/vulnerability/RUSTSEC-2026-0329) - - - Facts on this page come from the GitHub Advisory Database (CC-BY 4.0), OSV and the other sources listed, as published. We don’t reproduce full advisory descriptions, which can contain exploit code. ## Check whether this affects you A Match means an installed version is in the affected range above. Most don’t affect the app; agentprime hasn’t analysed this one yet. - With the agentprime MCP server (), ask your agent to check the project: `check_lockfile` sends a lockfile, `check_packages` a list of installed packages, and both return the Matches and the upgrades that clear them. `get_advisory` returns this record. Setup: - In a browser: reads your lockfile in the browser, never uploading it. - Whether it touches your code, with file and line: the Claude Code plugin, - As JSON: , or `POST https://api.agentprime.io/v1/match` with your packages () --- The web page: . Everything for agents: .