rkyv: Panic safety bugs in InlineVec::clear and SerVec::clear enable arbitrary code execution

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS 4.0

6.9 · CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N · score source

EPSS

No dated EPSS signal available.

As published by the source; long descriptions are shortened.

InlineVec::clear() and SerVec::clear() in rkyv were not panic-safe. Both functions iterate over their elements and call dropinplace on each, updating self.len only after the loop. If an element's Drop implementation panics during the loop, self.len is left at its original value. A subsequent invocation of clear() on the same container then re-visits the already-freed elements: - InlineVec::clear() is called again from InlineVec's own Drop implementation when the value is later dropped. - SerVec::clear() is called again by SerVec::withcapacity() after the user closure returns. Technical Impact - CWE-415 (Double Free): Heap corruption when element type holds Box<T - CWE-416 (Use-After-Free): Memory corruption when element reads from heap during Drop Both vulnerabilities are triggerable entirely from safe Rust via std::panic::catchunwind and require no special privileges.

Published by the source

15 May 2026, 18:09 UTC

Last modified by the source

15 May 2026, 18:09 UTC

Source last checked

26 Oct 2026, 15:42 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-vfvv-c25p-m7mm

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# Patch Next advisory brief: GHSA-vfvv-c25p-m7mm

Advisory: rkyv: Panic safety bugs in `InlineVec::clear` and `SerVec::clear` enable arbitrary code execution
IDs: GHSA-vfvv-c25p-m7mm
Record: https://patchnext.com/advisories/ghsa-vfvv-c25p-m7mm (revision 1, source checked 26 Oct 2026, 15:42 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 6.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: rkyv 0.8.16. A vendor fix does not mean a deployment is fixed.

## Affected components
- crates.io rkyv: affected >= 0.8.0, < 0.8.16; fixed in 0.8.16

## Suggested inspection (read-only)
- crates.io rkyv: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on rkyv.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-vfvv-c25p-m7mm (GitHub-reviewed advisory GHSA-vfvv-c25p-m7mm lists affected ranges: crates.io rkyv >=0.8.0 <0.8.16)

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