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Advisory details: vulnrichment / CVE-2026-48747
Advisory ID vulnrichment/CVE-2026-48747
Aliases
Summary Symfony is a PHP framework for web and console applications and a set of reusable PHP components. Prior to 7.4.13 and 8.0.13, MailomatRequestParser::validateSignature() parsed X-MOM-Webhook-Signature as algo=signature and passed the request-selected algorithm to hash_hmac(), allowing a signature algorithm downgrade instead of enforcing Mailomat's documented SHA-256 webhook signature. This issue is fixed in versions 7.4.13 and 8.0.13.
Status Published
Exploitability 0.5
Weighted Severity 0.0
Risk
Affected and Fixed Packages Package Details
Introduced and Fixed Package Commit Patches Package Commit Patches Details
Weaknesses (2)
CWE-347 Improper Verification of Cryptographic Signature
CWE-757 Selection of Less-Secure Algorithm During Negotiation ('Algorithm Downgrade')
System Score Found at
cvssv4 6.3
ssvc Track
Reference id Reference type URL
https://github.com/symfony/symfony/commit/bdfe9fe0d94d33dfaca0bc2fe0b00b54767b0c88
https://github.com/symfony/symfony/security/advisories/GHSA-rrj9-5q2j-4gvr
v7.4.13 Other https://github.com/symfony/symfony/releases/tag/v7.4.13
v8.0.13 Other https://github.com/symfony/symfony/releases/tag/v8.0.13
No exploits are available.

No EPSS data available for this advisory.

Patch URL
There are no known patches.
Vector: CVSS:4.0/AV:N/AC:H/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N Found at None
Attack Vector (AV) Attack Complexity (AC) Attack Requirements (AT) Privileges Required (PR) User Interaction (UI) Vulnerable System Impact Confidentiality (VC) Vulnerable System Impact Integrity (VI) Vulnerable System Impact Availability (VA) Subsequent System Impact Confidentiality (SC) Subsequent System Impact Integrity (SI) Subsequent System Impact Availability (SA)

network

adjacent

local

physical

low

high

none

present

none

low

high

none

passive

active

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none

high

low

none
Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-07-15T14:22:33Z/ Found at None

Vector: SSVCv2/E:N/A:N/T:P/P:M/B:A/M:M/D:T/2026-07-15T14:22:33Z/

Decision: Track

Source URL: https://github.com/cisagov/vulnrichment/blob/develop/2026/48xxx/CVE-2026-48747.json

Source Advisory: vulnrichment/CVE-2026-48747

View SSVC decision tree 
[{'Exploitation': 'none'},
 {'Automatable': 'no'},
 {'Technical Impact': 'partial'},
 {'Mission Prevalence': 'minimal'},
 {'Public Well-being Impact': 'material'},
 {'Mission & Well-being': 'medium'}]