---
title: "CVE-2016-6129\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2016-6129?format=md
keywords: index, follow
---

# CVE-2016-6129

Publication date 13 February 2017

Last updated 11 September 2026

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2016-6129?format=md#impact-score)

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## Description

The rsa\_verify\_hash\_ex function in rsa\_verify\_hash.c in LibTomCrypt, as
used in OP-TEE before 2.2.0, does not validate that the message length is
equal to the ASN.1 encoded data length, which makes it easier for remote
attackers to forge RSA signatures or public certificates by leveraging a
Bleichenbacher signature forgery attack.

### From the Ubuntu Security Team

It was discovered that LibTomCrypt incorrectly handled RSA signatures or
public certificates. An attacker could possibly use this issue to make a
Bleichenbacher signature forgery attack.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2016-6129?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| libtomcrypt | 18.04 LTS bionic | Not affected |
| 17.10 artful | Ignored end of life |
| 17.04 zesty | Ignored end of life |
| 16.10 yakkety | Ignored end of life |
| 16.04 LTS xenial | Fixed 1.17-7ubuntu0.1 |
| 14.04 LTS trusty | Fixed 1.17-5ubuntu0.1 |
| 12.04 LTS precise | Fixed 1.17-3.2+deb7u1ubuntu0.1 |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

## Notes

---

### [tyhicks](https://launchpad.net/~tyhicks)

Per Debian's security tracker, the underlying issue looks to be in
libtomcrypt

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Network |
  | Attack complexity | Low |
  | Privileges required | None |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | None |
  | Integrity impact | High |
  | Availability impact | None |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2016-6129)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2016-6129)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2016-6129)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2016-6129)

### Other references

* <https://github.com/OP-TEE/optee_os/commit/30d13250c390c4f56adefdcd3b64b7cc672f9fe2>
* <https://github.com/libtom/libtomcrypt/commit/5eb9743410ce4657e9d54fef26a2ee31a1b5dd09>
* <https://www.cve.org/CVERecord?id=CVE-2016-6129>