CVE-2026-48747GHSA-RRJ9-5Q2J-4GVR
Symfony: Mailomat Mailer Webhook Parser Reads the HMAC Algorithm from the Request: Signature Algorithm Downgrade
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 7.4.12, 8.0.13, 7.4.13
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
CISA's decision points: whether it is exploited, whether attacks can be automated, and how much control an attacker gets. Assessed (SSVC 2.0.3).What do these mean? →
- Exploitation: none
- Automatable: no
- Technical impact: partial
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.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: no · Technical impact: partial
- Record last updated
Affected versions
- symfony symfony
From 7.2.0 · fixed in 7.4.12; From 8.0.0-BETA1 · fixed in 8.0.13
- symfony mailomat-mailer
From 7.2.0 · fixed in 7.4.12; From 8.0.0-BETA1 · fixed in 8.0.13
- symfony/mailomat-mailerPackagist
From 7.2.0 · fixed in 7.4.13
- symfony/mailomat-mailerPackagist
From 8.0.0 · fixed in 8.0.13
- symfony/symfonyPackagist
From 7.2.0 · fixed in 7.4.13
- symfony/symfonyPackagist
From 8.0.0 · fixed in 8.0.13