# CVE-2026-85088: Security feature bypass in Apache Thrift

> Attackers with a valid CA-signed certificate can bypass hostname verification in Apache Thrift C++ and D clients by exploiting Common Name fallback logic.

- **Severity:** Medium 6.9 (`CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:U`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** Yes
- **Published:** 2 Oct 2026
- **Updated:** 2 Oct 2026
- **Also known as:** AZL-106548, BIT-thrift-2026-85088, DEBIAN-CVE-2026-85088, ECHO-b211-92e6-3d9d, GHSA-4xmj-xwhr-jcj2, MINI-f29v-g78v-34m8, UBUNTU-CVE-2026-85088

## What is CVE-2026-85088?

CVE-2026-85088 is a medium-severity vulnerability in Apache Thrift, published on 2 Oct 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.

### Official description

Improper Validation of Certificate with Host Mismatch in the C++ and D libraries of Apache Thrift.

Both libraries install a default access manager for client sockets — TSSLSocketFactory does so in C++, and the accessManager property does so in D — which compares the peer certificate against the host

name that was connected to. That comparison walks the subjectAltName dNSName entries first and consults the certificate Common Name afterwards. A name that does not match yields a "skip" result rather than

a rejection, so a certificate whose subjectAltName entries are all present and all non-matching falls through to the Common Name, which can then satisfy the check.

RFC 6125 section 6.4.4, and RFC 9525 section 2, require that the Common Name is not consulted when a dNSName subjectAltName is present. A certificate carrying subjectAltName entries for one name and a

Common Name for another is therefore accepted for a connection to the second name.

Exploitation requires an attacker positioned on the network path who holds a certificate that chains to a certificate authority in the client's trust store and whose Common Name matches the connected host

name. Public certificate authorities have not issued on Common Name alone for many years, so this is principally a concern for deployments using a private or enterprise public-key infrastructure.

This issue affects the C++ library of Apache Thrift from 0.7.0 through 0.24.0 and the D library from 0.9.0 through 0.24.0. Users should upgrade to 0.25.0.

Weakness: CWE-297 (Improper Validation of Certificate with Host Mismatch), CWE-295 (Improper Certificate Validation)

## Which versions are affected by CVE-2026-85088?

1 open source package ship an affected version, including thrift.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `thrift` | Bitnami | All versions | 0.25.0 |

## How do I fix CVE-2026-85088?

Upgrade thrift to 0.25.0 or later.

## Is CVE-2026-85088 being exploited?

There is no known exploitation of CVE-2026-85088 in the wild and no public exploit code.

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-85088 and fix it if it is affected.

What it is: CVE-2026-85088 is a medium-severity vulnerability in Apache Thrift, published on 2 Oct 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-2026-85088 in the wild and no public exploit code.

Affected packages and fixed versions:
- thrift (Bitnami): affected all versions; fixed in 0.25.0

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-2026-85088/ (Markdown: https://insights.sbomify.com/CVE-2026-85088/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-85088
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-85088
- OSV: https://osv.dev/vulnerability/CVE-2026-85088

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-85088/
Summaries are generated and may contain mistakes; the official description above is the record.