Exim tls-openssl.c use after free

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.0$0-$5k0.00

Summaryinfo

A vulnerability classified as critical was found in Exim. Affected by this issue is some unknown functionality of the file tls-openssl.c. Executing a manipulation can lead to use after free. This vulnerability appears as CVE-2020-28018. The attack may be performed from remote. In addition, an exploit is available. A patch should be applied to remediate this issue.

Detailsinfo

A vulnerability classified as critical was found in Exim (Mail Server Software) (version unknown). This vulnerability affects an unknown function of the file tls-openssl.c. 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.

The weakness was presented 05/06/2021. The advisory is available at qualys.com. This vulnerability was named CVE-2020-28018. Technical details and also a public exploit are known.

A public exploit has been developed by LockedByte in C and been published 2 weeks after the advisory. It is possible to download the exploit at github.com. It is declared as proof-of-concept.

Applying a patch is able to eliminate this problem.

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

Productinfo

Type

Name

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 6.3
VulDB Meta Temp Score: 6.0

VulDB Base Score: 6.3
VulDB Temp Score: 6.0
VulDB Vector: 🔍
VulDB Reliability: 🔍

CVSSv2info

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

Exploitinginfo

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

Physical: No
Local: No
Remote: Yes

Availability: 🔍
Access: Public
Status: Proof-of-Concept
Author: LockedByte
Programming Language: 🔍
Download: 🔍

EPSS Score: 🔍
EPSS Percentile: 🔍

Price Prediction: 🔍
Current Price Estimation: 🔍

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Patch
Status: 🔍

0-Day Time: 🔍
Exploit Delay Time: 🔍

Timelineinfo

10/30/2020 🔍
05/06/2021 +187 days 🔍
05/06/2021 +0 days 🔍
05/15/2021 +8 days 🔍
05/15/2021 +0 days 🔍

Sourcesinfo

Advisory: qualys.com
Status: Confirmed

CVE: CVE-2020-28018 (🔍)
GCVE (CVE): GCVE-0-2020-28018
GCVE (VulDB): GCVE-100-174538
scip Labs: https://www.scip.ch/en/?labs.20161013

Entryinfo

Created: 05/06/2021 09:39
Updated: 05/15/2021 13:33
Changes: 05/06/2021 09:39 (35), 05/09/2021 08:43 (5), 05/15/2021 13:32 (6), 05/15/2021 13:33 (2)
Complete: 🔍
Committer: misc
Cache ID: 216::103

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

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