Apache HTTP Server 2.4.26 HTTP/2 free use after free

CVSS Meta Temp Score
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CTI Interest Score
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7.1$0-$5k0.00

Summaryinfo

A vulnerability was found in Apache HTTP Server 2.4.26. It has been classified as critical. Affected by this vulnerability is an unknown functionality of the component HTTP2 Handler. Performing a manipulation results in use after free (free). This vulnerability is identified as CVE-2017-9789. The attack can be initiated remotely. There is not any exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability, which was classified as critical, was found in Apache HTTP Server 2.4.26 (Web Server). This affects an unknown code block of the component HTTP2 Handler. The manipulation with an unknown input leads to a use after free vulnerability (Free). CWE is classifying the issue as CWE-416. Referencing memory after it has been freed can cause a program to crash, use unexpected values, or execute code. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

When under stress, closing many connections, the HTTP/2 handling code in Apache httpd 2.4.26 would sometimes access memory after it has been freed, resulting in potentially erratic behaviour.

The bug was discovered 07/11/2017. The weakness was released 07/13/2017 by Robert Swiecki (Website). The advisory is shared at lists.apache.org. This vulnerability is uniquely identified as CVE-2017-9789 since 06/21/2017. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Neither technical details nor an exploit are publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 101788 (Apache 2.4.x < 2.4.27 Multiple Vulnerabilities), which helps to determine the existence of the flaw in a target environment. It is assigned to the family Web Servers and running in the context r. The commercial vulnerability scanner Qualys is able to test this issue with plugin 370625 (Apple macOS High Sierra 10.13.1, Security Update 2017-001 Sierra, and Security Update 2017-004 El Capitan Not Installed).

Upgrading eliminates this vulnerability. A possible mitigation has been published before and not just after the disclosure of the vulnerability.

The vulnerability is also documented in the databases at Tenable (101788) and SecurityFocus (BID 99568†). Further details are available at seclists.org. Entries connected to this vulnerability are available at VDB-108927, VDB-108939, VDB-108940 and VDB-108941. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 7.4
VulDB Meta Temp Score: 7.2

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

NVD Base Score: 7.5
NVD Vector: 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Name: Free
Class: Use after free / 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: 101788
Nessus Name: Apache 2.4.x < 2.4.27 Multiple Vulnerabilities
Nessus File: 🔍
Nessus Risk: 🔍
Nessus Family: 🔍
Nessus Context: 🔍

OpenVAS ID: 800837
OpenVAS Name: Apache HTTP Server mod_http2 Denial-Of-Service Vulnerability (Windows)
OpenVAS File: 🔍
OpenVAS Family: 🔍

Qualys ID: 🔍
Qualys Name: 🔍

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

06/21/2017 🔍
07/11/2017 +20 days 🔍
07/11/2017 +0 days 🔍
07/13/2017 +2 days 🔍
07/13/2017 +0 days 🔍
07/13/2017 +0 days 🔍
07/14/2017 +1 days 🔍
07/18/2017 +4 days 🔍
01/01/2021 +1263 days 🔍

Sourcesinfo

Vendor: apache.org

Advisory: lists.apache.org
Researcher: Robert Swiecki
Status: Not defined
Confirmation: 🔍

CVE: CVE-2017-9789 (🔍)
GCVE (CVE): GCVE-0-2017-9789
GCVE (VulDB): GCVE-100-103521
SecurityFocus: 99568 - Apache HTTP Server CVE-2017-9789 Denial of Service Vulnerability
SecurityTracker: 1038907

Misc.: 🔍
See also: 🔍

Entryinfo

Created: 07/14/2017 10:41
Updated: 01/01/2021 11:46
Changes: 07/14/2017 10:41 (76), 10/25/2019 18:03 (6), 01/01/2021 11:46 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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