Description
Cap'n Proto is a data interchange format and remote procedure call (RPC) system. Cap'n Proro prior to versions 0.7.1, 0.8.1, 0.9.2, and 0.10.3, as well as versions of Cap'n Proto's Rust implementation prior to 0.13.7, 0.14.11, and 0.15.2 are vulnerable to out-of-bounds read due to logic error handling list-of-list. This issue may lead someone to remotely segfault a peer by sending it a malicious message, if the victim performs certain actions on a list-of-pointer type. Exfiltration of memory is possible if the victim performs additional certain actions on a list-of-pointer type. To be vulnerable, an application must perform a specific sequence of actions, described in the GitHub Security Advisory. The bug is present in inlined code, therefore the fix will require rebuilding dependent applications. Cap'n Proto has C++ fixes available in versions 0.7.1, 0.8.1, 0.9.2, and 0.10.3. The `capnp` Rust crate has fixes available in versions 0.13.7, 0.14.11, and 0.15.2.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| capnproto | capnproto | < 0.7.1, >= 0.8.0, < 0.8.1, >= 0.9.0, < 0.9.2, >= 0.10.0, < 0.10.3, >= 0.13.0, < 0.13.7, >= 0.14.0, < 0.14.11, >= 0.15.0, < 0.15.2 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | capnproto | 0.9.2-2 | — |
| Debian 14 | rust-capnp | 0.14.11-1.1 | — |
| Debian 13 | capnproto | 0.9.2-2 | — |
| Debian 13 | rust-capnp | 0.14.11-1.1 | — |
| Debian 12 | capnproto | 0.9.2-2 | — |
| Debian 12 | rust-capnp | 0.14.11-1.1 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 22.04 LTS | capnproto | No fix yet | — |
| Ubuntu 16.04 LTS | capnproto +1 | No fix yet | — |
| Ubuntu 14.04 LTS | capnproto | No fix yet | — |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 20.04 LTS | capnproto | No fix yet | — |
| Ubuntu Pro 18.04 LTS | capnproto | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Red Hat OpenShift 4 | conmon-rs | 0.5.1-3.rhaos4.12.git.el8 | RHSA-2023:1408 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP4 | capnproto | 0.9.1-150400.3.4.1 | SUSE-SU-2022:4478-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | python-pycapnp | 2.0.0-2.5 | openSUSE-SU-2025:15102-1 |
| openSUSE Leap 15.4 | capnproto | 0.9.1-150400.3.4.1 | SUSE-SU-2022:4478-1 |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| crates.io | capnp | >= 0.15.0, < 0.15.2 | 0.15.2 | GHSA-qqff-4vw4-f6hx |
| crates.io | capnp | >= 0.14.0, < 0.14.11 | 0.14.11 | GHSA-qqff-4vw4-f6hx |
| crates.io | capnp | < 0.13.7 | 0.13.7 | GHSA-qqff-4vw4-f6hx |
| crates.io | capnp | >= 0.0.0-0, < 0.13.7 · >= 0.14.0-0, < 0.14.11 · >= 0.15.0-0, < 0.15.2 | 0.13.7, 0.14.11, 0.15.2 | RUSTSEC-2022-0068 |
Advisories 4
- RHSA-2023:1408 Red Hat Security Advisory: OpenShift Container Platform 4.12.9 packages and security update Red Hat Security Advisories (RHSA) · Aug 7, 2026
- openSUSE-SU-2025:15102-1 python311-pycapnp-2.0.0-2.5 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2022:4478-1 Security update for capnproto SUSE / openSUSE Security Updates · Feb 4, 2026
- WID-SEC-2023-0775 Red Hat OpenShift: Schwachstelle ermöglicht Denial of Service BSI CERT-Bund (WID) · May 18, 2025
References
- https://github.com/capnproto/capnproto/security/advisories/GHSA-qqff-4vw4-f6hx
- https://github.com/capnproto/capnproto/commit/25d34c67863fd960af34fc4f82a7ca3362ee74b9
- FEDORA-2022-5d37367673 vendor-advisory
- FEDORA-2022-18023b665f vendor-advisory
- FEDORA-2022-fd7eeedd02 vendor-advisory
- FEDORA-2022-7002ec8b22 vendor-advisory