Cisco IOS XE up to 17.12.1a HTTP Server Telephony Service null pointer dereference

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.9$0-$5k0.00

Summaryinfo

A vulnerability has been found in Cisco IOS XE and classified as critical. This issue affects some unknown processing of the component HTTP Server Telephony Service. This manipulation causes null pointer dereference. This vulnerability is handled as CVE-2024-20436. The attack can be initiated remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability has been found in Cisco IOS XE and classified as critical. Affected by this vulnerability is an unknown part of the component HTTP Server Telephony Service. The manipulation with an unknown input leads to a null pointer dereference vulnerability. The CWE definition for the vulnerability is CWE-476. A NULL pointer dereference occurs when the application dereferences a pointer that it expects to be valid, but is NULL, typically causing a crash or exit. As an impact it is known to affect availability. The summary by CVE is:

A vulnerability in the HTTP Server feature of Cisco IOS XE Software when the Telephony Service feature is enabled could allow an unauthenticated, remote attacker to cause a denial of service (DoS) condition on an affected device. This vulnerability is due to a null pointer dereference when accessing specific URLs. An attacker could exploit this vulnerability by sending crafted HTTP traffic to an affected device. A successful exploit could allow the attacker to cause the affected device to reload, causing a DoS condition on the affected device.

It is possible to read the advisory at sec.cloudapps.cisco.com. This vulnerability is known as CVE-2024-20436 since 11/08/2023. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. The technical details are unknown and an exploit is not publicly available. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/27/2024).

The vulnerability scanner Nessus provides a plugin with the ID 207824 (Cisco IOS XE Software HTTP Server Telephony Services DoS (cisco-sa-httpsrvr-dos-yOZThut)), which helps to determine the existence of the flaw in a target environment.

Upgrading eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at Tenable (207824). Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

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Vendor

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 8.0
VulDB Meta Temp Score: 7.9

VulDB Base Score: 7.5
VulDB Temp Score: 7.2
VulDB Vector: 🔍
VulDB Reliability: 🔍

CNA Base Score: 8.6
CNA Vector (cisco): 🔍

CVSSv2info

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

Exploitinginfo

Class: Null pointer dereference
CWE: CWE-476 / CWE-404
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: 207824
Nessus Name: Cisco IOS XE Software HTTP Server Telephony Services DoS (cisco-sa-httpsrvr-dos-yOZThut)

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔍

Timelineinfo

11/08/2023 🔍
09/25/2024 +321 days 🔍
09/25/2024 +0 days 🔍
09/27/2024 +2 days 🔍

Sourcesinfo

Vendor: cisco.com

Advisory: cisco-sa-httpsrvr-dos-yOZThut
Status: Confirmed

CVE: CVE-2024-20436 (🔍)
GCVE (CVE): GCVE-0-2024-20436
GCVE (VulDB): GCVE-100-278491
scip Labs: https://www.scip.ch/en/?labs.20150108

Entryinfo

Created: 09/25/2024 18:48
Updated: 09/27/2024 17:37
Changes: 09/25/2024 18:48 (65), 09/27/2024 17:37 (2)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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