CVE-2021-32693 | Authentication granted with multiple firewalls

Symfony is a PHP framework for web and console applications and a set of reusable PHP components. A vulnerability related to firewall authentication is in Symfony starting with version 5.3.0 and prior to 5.3.2. When an application defines multiple firewalls, the token authenticated by one of the firewalls was available for all other firewalls. This could be abused when the application defines different providers for each part of the application, in such a situation, a user authenticated on a part of the application could be considered authenticated on the rest of the application. Starting in version 5.3.2, a patch ensures that the authenticated token is only available for the firewall that generates it.

Published: 2021-06-17 Last update: 2024-11-21 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2021-32693 is rated Moderate Risk (42.4/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.22%). Mandatory action: Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2021-32693

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-05-31 0.55% 0.22% -0.33%
2 2025-05-16 0.43% 0.55% +0.11%
3 2025-03-30 0.43%

Full EPSS history (12 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2021-32693

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
6.8 3.1 MEDIUM
CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:H)
Even with access, the exploit needs extra luck, timing, or a fussy environment to actually work.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:N)
Service keeps running; no real outage angle.
1.6 5.2 [email protected]
8.8 3.1 HIGH
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:L)
A normal user session is enough; they don’t have to be admin.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
2.8 5.9 [email protected]
6.5 2.0 MEDIUM
AV:N/AC:L/Au:S/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:L)
Exploitation conditions are straightforward and predictable.
Authentication (AU:S)
A single authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
8.0 6.4 [email protected]

Weakness enumeration for CVE-2021-32693

GitHub Security Advisory for CVE-2021-32693

GHSA-rfcf-m67m-jcrq · Severity: medium · Ecosystem: composer — Authentication granted to all firewalls instead of just one

OS Trackers for CVE-2021-32693

vendor priority summary link
debian unimportant CVE-2021-32693 unimportant priority: Debian including 1 source packages (symfony), 5 status rows across 5 suites (bookworm, bullseye, forky, sid, trixie): resolved 5. https://security-tracker.debian.org/tracker/CVE-2021-32693
ubuntu medium CVE-2021-32693 medium priority: Ubuntu including 1 source packages (symfony), 9 status rows across 9 suites (bionic, focal, groovy, hirsute, impish, jammy, trusty, upstream, xenial): not-affected 5, ignored 2, DNE 1, needs-triage 1. https://ubuntu.com/security/CVE-2021-32693

Affected software / configurations for CVE-2021-32693

Vendor Product Version Raw CPE
sensiolabs symfony >= 5.3.0, < 5.3.2 cpe:2.3:a:sensiolabs:symfony:*:*:*:*:*:*:*:*

References for CVE-2021-32693

cvelogic Threat Intelligence