# CVE-2026-41565: CryptX versions before 0.088_001 for Perl have a stack buffer overflow in four AEAD decrypt_verify helpers

> A stack buffer overflow in CryptX AEAD helpers allows attackers to execute arbitrary code or cause denial of service via long authentication tags.

- **Severity:** High 7.5 (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 28 May 2026
- **Updated:** 29 May 2026
- **Also known as:** DEBIAN-CVE-2026-41565, GHSA-4p3p-7392-hjw4, UBUNTU-CVE-2026-41565, openSUSE-SU-2026:10968-1

## What is CVE-2026-41565?

CVE-2026-41565 is a high-severity memory corruption vulnerability in MIK CryptX, published on 28 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

CryptX versions before 0.088_001 for Perl have a stack buffer overflow in four AEAD decrypt_verify helpers.

The gcm_decrypt_verify, ccm_decrypt_verify, chacha20poly1305_decrypt_verify and eax_decrypt_verify XS routines copied the caller-supplied authentication tag into a fixed 144-byte stack buffer (MAXBLOCKSIZE) without checking the supplied length. A longer tag overwrites the stack past the buffer. Version 0.088 added the clamp to gcm_decrypt_verify, and 0.088_001 added it to the other three.

Any caller of an affected helper that forwards an attacker-controlled tag longer than the buffer can trigger the overflow.

Weakness: CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2026-41565?


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `perl-CryptX` | openSUSE:Tumbleweed | All versions | 0.89.0-2.1 |

## How do I fix CVE-2026-41565?

Upgrade to a fixed version.

## Is CVE-2026-41565 being exploited?

There is no known exploitation of CVE-2026-41565 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-41565 and fix it if it is affected.

What it is: CVE-2026-41565 is a high-severity memory corruption vulnerability in MIK CryptX, published on 28 May 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-41565 in the wild and no public exploit code.

Affected product: MIK CryptX. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-41565/ (Markdown: https://insights.sbomify.com/CVE-2026-41565/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-41565
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-41565
- OSV: https://osv.dev/vulnerability/CVE-2026-41565

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-41565/
Summaries are generated and may contain mistakes; the official description above is the record.