cURL up to 7.54.1 TFTP URL tftp.c tftp_send_first filename Memory information disclosure

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k0.00

A vulnerability classified as problematic was found in cURL up to 7.54.1 (Network Utility Software). Affected by this vulnerability is the function tftp_send_first of the file tftp.c of the component TFTP URL Handler. The manipulation of the argument filename with an unknown input leads to a information disclosure vulnerability (Memory). The CWE definition for the vulnerability is CWE-200. The product exposes sensitive information to an actor that is not explicitly authorized to have access to that information. As an impact it is known to affect confidentiality.

The bug was discovered 07/11/2017. The weakness was presented 08/09/2017 as adv_20170809B as confirmed advisory (Website). It is possible to read the advisory at curl.haxx.se. This vulnerability is known as CVE-2017-1000100 since 10/03/2017. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1592 according to MITRE ATT&CK.

The vulnerability was handled as a non-public zero-day exploit for at least 29 days. During that time the estimated underground price was around $0-$5k. The vulnerability scanner Nessus provides a plugin with the ID 102877 (Amazon Linux AMI : curl (ALAS-2017-889)), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Amazon Linux Local Security Checks and running in the context l. The commercial vulnerability scanner Qualys is able to test this issue with plugin 351077 (Amazon Linux Security Advisory for curl: ALAS-2017-889).

Upgrading to version 7.55.0 eliminates this vulnerability. Applying a patch is able to eliminate this problem. The bugfix is ready for download at curl.haxx.se. The best possible mitigation is suggested to be upgrading to the latest version. A possible mitigation has been published immediately after the disclosure of the vulnerability. The vulnerability will be addressed with the following lines of code:

if(strlen(filename) > (state->blksize - strlen(mode) - 4)) {
   failf(data, "TFTP file name too long\n");
   return CURLE_TFTP_ILLEGAL; /* too long file name field */
}

The vulnerability is also documented in the vulnerability database at Tenable (102877). See 105282, 105284 and 108947 for similar entries.

Productinfo

Type

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB CVSS-B Score: 🔍
VulDB CVSS-BT Score: 🔍
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔍
VulDB Reliability: 🔍

NVD Base Score: 6.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Name: Memory
Class: Information disclosure / Memory
CWE: CWE-200 / CWE-284 / CWE-266
CAPEC: 🔍
ATT&CK: 🔍

Local: No
Remote: Yes

Availability: 🔍
Status: Not defined

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Nessus ID: 102877
Nessus Name: Amazon Linux AMI : curl (ALAS-2017-889)
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 53378
OpenVAS Name: Debian Security Advisory DSA 3992-1 (curl - security update)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

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

Upgrade: cURL 7.55.0
Patch: curl.haxx.se

Timelineinfo

07/11/2017 🔍
08/09/2017 +29 days 🔍
08/09/2017 +0 days 🔍
08/09/2017 +0 days 🔍
08/10/2017 +1 days 🔍
08/13/2017 +3 days 🔍
09/01/2017 +19 days 🔍
10/03/2017 +32 days 🔍
10/04/2017 +1 days 🔍
01/09/2021 +1193 days 🔍

Sourcesinfo

Advisory: adv_20170809B
Researcher: Even Rouault.
Status: Confirmed
Confirmation: 🔍

CVE: CVE-2017-1000100 (🔍)
OVAL: 🔍

SecurityTracker: 1039118
SecurityFocus: 100286 - cURL/libcURL CVE-2017-1000100 Heap Based Buffer Overflow Vulnerability

See also: 🔍

Entryinfo

Created: 08/13/2017 19:28
Updated: 01/09/2021 11:44
Changes: 08/13/2017 19:28 (86), 11/06/2019 17:59 (5), 01/09/2021 11:41 (2), 01/09/2021 11:44 (1)
Complete: 🔍
Cache ID: 3:6B8:103

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