Detection rules › Sigma

Old TLS1.0/TLS1.1 Protocol Version Enabled

Status
test
Severity
medium
Log source
product windows, category registry_set
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects applications or users re-enabling old TLS versions by setting the "Enabled" value to "1" for the "Protocols" registry key.

MITRE ATT&CK coverage

TacticTechniques
StealthNo specific technique

Event coverage

ProviderEventTitle
SysmonEvent ID 13RegistryEvent (Value Set)

Rule body yaml

title: Old TLS1.0/TLS1.1 Protocol Version Enabled
id: 439957a7-ad86-4a8f-9705-a28131c6821b
status: test
description: Detects applications or users re-enabling old TLS versions by setting the "Enabled" value to "1" for the "Protocols" registry key.
references:
    - https://techcommunity.microsoft.com/t5/windows-it-pro-blog/tls-1-0-and-tls-1-1-soon-to-be-disabled-in-windows/ba-p/3887947
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-09-05
tags:
    - attack.stealth
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|contains:
            - '\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\'
            - '\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\'
        TargetObject|endswith: '\Enabled'
        Details: 'DWORD (0x00000001)'
    condition: selection
falsepositives:
    - Legitimate enabling of the old tls versions due to incompatibility
level: medium

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetObject|contains:
        - '\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\'
        - '\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\'
    TargetObject|endswith: '\Enabled'
    Details: 'DWORD (0x00000001)'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Detailseq
  • DWORD (0x00000001) corpus 40 (sigma 36, chronicle 4)
TargetObjectends_with
  • \Enabled corpus 3 (sigma 3)
TargetObjectmatch
  • \Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.0\
  • \Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.1\