Envoy up to 1.9.0 Zero Character Header input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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7.4$0-$5k0.00

Summaryinfo

A vulnerability identified as critical has been detected in Envoy up to 1.9.0. Impacted is an unknown function of the component Zero Character Handler. Performing a manipulation as part of Header results in input validation. This vulnerability was named CVE-2019-9900. The attack may be initiated remotely. There is no available exploit.

Detailsinfo

A vulnerability classified as critical has been found in Envoy up to 1.9.0. This affects some unknown functionality of the component Zero Character Handler. The manipulation as part of a Header leads to a input validation vulnerability. CWE is classifying the issue as CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

When parsing HTTP/1.x header values, Envoy 1.9.0 and before does not reject embedded zero characters (NUL, ASCII 0x0). This allows remote attackers crafting header values containing embedded NUL characters to potentially bypass header matching rules, gaining access to unauthorized resources.

The bug was discovered 03/30/2019. The weakness was presented 04/25/2019 (Website). The advisory is shared at access.redhat.com. This vulnerability is uniquely identified as CVE-2019-9900 since 03/21/2019. 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 was handled as a non-public zero-day exploit for at least 26 days. During that time the estimated underground price was around $0-$5k.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

See VDB-134074 for similar entry. Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

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

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

NVD Base Score: 8.3
NVD Vector: 🔍

CNA Base Score: 6.5
CNA Vector (MITRE): 🔍

CVSSv2info

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

NVD Base Score: 🔍

Exploitinginfo

Class: Input validation
CWE: CWE-20
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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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔍

Timelineinfo

03/21/2019 🔍
03/30/2019 +9 days 🔍
04/25/2019 +26 days 🔍
04/26/2019 +1 days 🔍
09/07/2023 +1595 days 🔍

Sourcesinfo

Advisory: RHSA-2019:0741
Status: Not defined
Confirmation: 🔍

CVE: CVE-2019-9900 (🔍)
GCVE (CVE): GCVE-0-2019-9900
GCVE (VulDB): GCVE-100-134073
See also: 🔍

Entryinfo

Created: 04/26/2019 07:17
Updated: 09/07/2023 09:17
Changes: 04/26/2019 07:17 (57), 06/02/2020 11:44 (1), 09/07/2023 09:14 (3), 09/07/2023 09:17 (12)
Complete: 🔍
Cache ID: 216::103

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

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