cURL up to 7.61.1 Easy Curl_close use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.0$0-$5k0.00

Summaryinfo

A vulnerability was found in cURL up to 7.61.1. It has been declared as critical. This affects the function Curl_close of the component Easy Handler. Executing a manipulation can lead to use after free. This vulnerability is registered as CVE-2018-16840. It is possible to launch the attack remotely. No exploit is available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability classified as critical was found in cURL up to 7.61.1 (Network Utility Software). This vulnerability affects the function Curl_close of the component Easy Handler. The manipulation with an unknown input leads to a use after free vulnerability. The CWE definition for the vulnerability is CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. As an impact it is known to affect confidentiality, integrity, and availability. CVE summarizes:

A heap use-after-free flaw was found in curl versions from 7.59.0 through 7.61.1 in the code related to closing an easy handle. When closing and cleaning up an 'easy' handle in the `Curl_close()` function, the library code first frees a struct (without nulling the pointer) and might then subsequently erroneously write to a struct field within that already freed struct.

The bug was discovered 10/31/2018. The weakness was published 10/30/2018 by Brian Carpenter with Tencent as confirmed bug report (Bugzilla). The advisory is available at bugzilla.redhat.com. This vulnerability was named CVE-2018-16840 since 09/11/2018. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. Technical details are known, but there is no available exploit.

The vulnerability scanner Nessus provides a plugin with the ID 118591 (Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 18.10 : curl vulnerabilities (USN-3805-1)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Ubuntu Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 197290 (Ubuntu Security Notification for Curl Vulnerabilities (USN-3805-1)).

Upgrading eliminates this vulnerability. A possible mitigation has been published 2 hours after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (118591) and SecurityFocus (BID 106950†). Similar entries are available at VDB-110394, VDB-115419, VDB-126369 and VDB-126371. If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.1
VulDB Meta Temp Score: 7.0

VulDB Base Score: 7.3
VulDB Temp Score: 7.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 9.8
NVD Vector: 🔍

CNA Base Score: 4.3
CNA Vector: 🔍

CVSSv2info

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VulDB Base Score: 🔍
VulDB Temp Score: 🔍
VulDB Reliability: 🔍

NVD Base Score: 🔍

Exploitinginfo

Class: Use after free
CWE: CWE-416 / CWE-119
CAPEC: 🔍
ATT&CK: 🔍

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 118591
Nessus Name: Ubuntu 14.04 LTS / 16.04 LTS / 18.04 LTS / 18.10 : curl vulnerabilities (USN-3805-1)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

Reaction Time: 🔍
0-Day Time: 🔍
Exposure Time: 🔍

Patch: github.com

Timelineinfo

09/11/2018 🔍
10/30/2018 +50 days 🔍
10/31/2018 +0 days 🔍
10/31/2018 +0 days 🔍
10/31/2018 +0 days 🔍
11/01/2018 +1 days 🔍
11/01/2018 +0 days 🔍
02/06/2019 +97 days 🔍
04/17/2025 +2262 days 🔍

Sourcesinfo

Product: github.com

Advisory: USN-3805-1
Researcher: Brian Carpenter
Organization: Tencent
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2018-16840 (🔍)
GCVE (CVE): GCVE-0-2018-16840
GCVE (VulDB): GCVE-100-126370
SecurityFocus: 106950 - cURL/libcURL Multiple Buffer Overflow Vulnerabilities
SecurityTracker: 1042013

See also: 🔍

Entryinfo

Created: 11/01/2018 06:20
Updated: 04/17/2025 15:22
Changes: 11/01/2018 06:20 (72), 04/09/2020 12:04 (8), 06/04/2023 09:14 (6), 04/17/2025 15:22 (26)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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