# CVE-2026-50012: Squid: Memory corruption in cache_digest reply handling

> A heap-based buffer overflow in Squid allows a trusted peer to execute code or cause denial of service via malicious cache digest replies.

- **Severity:** Medium 5.5 (`CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:H`)
- **Exploited in the wild:** Not known
- **Login needed:** An administrator
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 16 Jul 2026
- **Updated:** 17 Jul 2026
- **Also known as:** ALPINE-CVE-2026-50012, AZL-92447, DEBIAN-CVE-2026-50012, GHSA-5vmx-9x64-9284, MINI-pcfw-mr37-wfhc, UBUNTU-CVE-2026-50012

## What is CVE-2026-50012?

CVE-2026-50012 is a medium-severity memory corruption vulnerability in Squid-Cache Squid, published on 16 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.

### Official description

Squid is a caching proxy for the Web. Prior to 7.6, due to an improper input validation bug in cache digest reply handling (peerDigestSwapInMask in src/peer_digest.cc), Squid is vulnerable to a heap-based buffer overflow: a cache digest's on-the-wire size may be larger than the mask_size declared within the digest, so a trusted peer sending a maliciously crafted reply to a cache_digest request message can trigger the overflow. This attack is limited to Squid instances compiled with the --enable-cache-digests option and configured with cache_peer entries. This issue is fixed in version 7.6.

Weakness: CWE-20 (Improper Input Validation), CWE-122 (Heap-based Buffer Overflow)

## Which versions are affected by CVE-2026-50012?

It affects 1 product.


Products: Squid-Cache Squid.

## How do I fix CVE-2026-50012?

Upgrade to a fixed version.

## Is CVE-2026-50012 being exploited?

There is no known exploitation of CVE-2026-50012 in the wild and no public exploit code.

## Other vulnerabilities in Squid-Cache Squid

- [CVE-2025-62168](https://insights.sbomify.com/CVE-2025-62168/): Squid vulnerable to information disclosure via authentication credential leakage in error handling (critical 10.0)
- [CVE-2025-54574](https://insights.sbomify.com/CVE-2025-54574/): Squid's URN Handling can lead to Buffer Overflow (critical 9.3)
- [CVE-2026-33526](https://insights.sbomify.com/CVE-2026-33526/): Squid vulnerable to Denial of Service in ICP Request handling (critical 9.2)
- [CVE-2026-32748](https://insights.sbomify.com/CVE-2026-32748/): Squid has Denial of Service in ICP Response handling (high 8.7)
- [CVE-2023-50269](https://insights.sbomify.com/CVE-2023-50269/): SQUID-2023:10 Denial of Service in HTTP Request parsing (high 8.6)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-50012 and fix it if it is affected.

What it is: CVE-2026-50012 is a medium-severity memory corruption vulnerability in Squid-Cache Squid, published on 16 Jul 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-50012 in the wild and no public exploit code.

Affected product: Squid-Cache Squid. 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-2026-50012/ (Markdown: https://insights.sbomify.com/CVE-2026-50012/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-50012
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-50012
- OSV: https://osv.dev/vulnerability/CVE-2026-50012

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-50012/
Summaries are generated and may contain mistakes; the official description above is the record.