---
title: "CVE-2017-7468\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-2017-7468?format=md
keywords: index, follow
---

# CVE-2017-7468

Publication date 19 April 2017

Last updated 25 August 2025

---

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-2017-7468?format=md#impact-score)

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## Description

In curl and libcurl 7.52.0 to and including 7.53.1, libcurl would attempt
to resume a TLS session even if the client certificate had changed. That is
unacceptable since a server by specification is allowed to skip the client
certificate check on resume, and may instead use the old identity which was
established by the previous certificate (or no certificate). libcurl
supports by default the use of TLS session id/ticket to resume previous TLS
sessions to speed up subsequent TLS handshakes. They are used when for any
reason an existing TLS connection couldn't be kept alive to make the next
handshake faster. This flaw is a regression and identical to CVE-2016-5419
reported on August 3rd 2016, but affecting a different version range.

### From the Ubuntu Security Team

It was discovered that curl incorrectly handled client certificates
when resuming a TLS session. A remote attacker could use this to hijack
a previously authenticated connection.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2017-7468?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| curl | 17.04 zesty | Fixed 7.52.1-4ubuntu1.1 |
| 16.10 yakkety | Not affected |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |
| 12.04 LTS precise | Not affected |

---

* [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

---

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

reported upstream mitigation:
Set `CURLOPT\_SSL\_SESSIONID\_CACHE` to 0L when using client certificates

## 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:3.0/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-2017-7468)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2017-7468)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2017-7468)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2017-7468)

### Related Ubuntu Security Notices (USN)

+ [USN-3262-1](https://usn.ubuntu.com/USN-3262-1)
+ curl vulnerability
+ 20 April 2017

### Other references

* <https://curl.haxx.se/docs/adv_20170419.html>
* <https://www.cve.org/CVERecord?id=CVE-2017-7468>