CVE-2020-5274: Exceptions displayed in non-debug configurations in Symfony
Noroxi assessment
Priority: Monitor (action score 21/100)
- The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
- Probability of exploitation in the next 30 days: 1.1% (FIRST EPSS); higher than 67.9% of all records.
- Anyone who can reach it over the internet can trigger it. A low-privileged account is enough. No user action is required. No special conditions are required; it is repeatable.
- Fixed version: symfony (Debian:12) 4.4.8-1; symfony/error-handler (Packagist) 4.4.4, 5.0.4; symfony/symfony (Packagist) 4.4.4, 5.0.4.
Low priority for now. Upgrade to symfony (Debian:12) 4.4.8-1; symfony/error-handler (Packagist) 4.4.4, 5.0.4; symfony/symfony (Packagist) 4.4.4, 5.0.4 or later.
Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it
Primary sources: NVD · CVE.org · FIRST EPSS
In Symfony before versions 5.0.5 and 4.4.5, some properties of the Exception were not properly escaped when the `ErrorHandler` rendered it stacktrace. In addition, the stacktrace were displayed even in a non-debug configuration. The ErrorHandler now escape alls properties of the exception, and the stacktrace is only display in debug configuration. This issue is patched in symfony/http-foundation versions 4.4.5 and 5.0.5
- Published
- Mar 30, 2020
- Updated
- Jun 16, 2026
- EPSS
- 1.1% · 67th percentile
- CWE
- CWE-209
Report tools
Action score
21
Monitor
Low priority for now.
- CVSS
- 21 / 40 · 5.4 / 10
- CISA KEV
- 0 / 30 · Not listed
- EPSS
- 0 / 30 · 1.1%
CNA vs NVD score
- NVD
- 5.4
- CNA · GitHub_M
- 4.6
- 0.8 point gap
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.
Get told when this record changes
- Not in KEV: no record of exploitation in the wild
- No public exploit code on record
- A fix has been released
If any of these changes, we'll tell you in the daily email digest.
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Noroxi analysis
What does it mean in your environment?
The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.
We use this product, ask for helpAffected systems
Is your version affected?
Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.
| Vendor | Product | CPE |
|---|---|---|
| sensiolabs | symfony | cpe:2.3:a:sensiolabs:symfony |
Affected versions
NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.
- sensiolabs symfony4.4.0 and later · before 4.4.4
- sensiolabs symfony5.0.0 and later · before 5.0.4
Versions reported by the vendor
Affected version ranges reported by the assigning authority (GitHub_M). Independent of NVD's CPE analysis and usually ahead of it.
symfony symfony
- >= 4.0.0, < 4.4.5, >= 5.0.0, < 5.0.5affected
Package-level exposure
OSV and GitHub Advisory data: ecosystem, package and range. SBOM matching uses this table.
| Ecosystem | Package | Affected range | Fix |
|---|---|---|---|
| Debian:12 | symfony | before 4.4.8-1 | 4.4.8-1 |
| Packagist | symfony/error-handler | from 4.4.0 · before 4.4.4 | 4.4.4 |
| Packagist | symfony/error-handler | from 5.0.0 · before 5.0.4 | 5.0.4 |
| Packagist | symfony/symfony | from 4.4.0 · before 4.4.4 | 4.4.4 |
| Packagist | symfony/symfony | from 5.0.0 · before 5.0.4 | 5.0.4 |
Same product
sensiolabs: all recordsOther highest-scoring records for the same primary product.
- CVE-2019-18889An issue was discovered in Symfony 3.4.0 through 3.4.34, 4.2.0 through 4.2.11, and 4.3.0 through 4.3.7.49Plan
- CVE-2018-14773An issue was discovered in Http Foundation in Symfony 2.7.0 through 2.7.48, 2.8.0 through 2.8.43, 3.3.0 through 3.3.17, 3.4.0 through 3.4.1343Plan
- CVE-2019-10910In Symfony before 2.7.51, 2.8.x before 2.8.50, 3.x before 3.4.26, 4.x before 4.1.12, and 4.2.x before 4.2.7, when service ids allow user inp41Plan
Published before and after this one in the same product
- ← EarlierCVE-2013-4752Jan 2, 2020 · Symfony 2.0.X before 2.0.24, 2.1.X before 2.1.12, 2.2.X before 2.2.5, and 2.3.X before 2.3.3 have an issue in the HttpFoundation component.25Monitor
- ← EarlierCVE-2020-5255Mar 30, 2020 · Prevent cache poisoning via a Response Content-Type header17Monitor
- Later →CVE-2020-5275Mar 30, 2020 · Firewall configured with unanimous strategy was not actually unanimous in symfony/security-http32Monitor
Remediation
Which version to upgrade to
Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.
| Product / package | Fixed version | Source |
|---|---|---|
| debian:symfony | 4.4.8-1 · Debian:12 | Package registry (OSV) |
| Packagist:symfony/error-handler | 4.4.4 | Package registry (OSV) |
| Packagist:symfony/error-handler | 5.0.4 | Package registry (OSV) |
| Packagist:symfony/symfony | 4.4.4 | Package registry (OSV) |
| Packagist:symfony/symfony | 5.0.4 | Package registry (OSV) |
Exploit status
No known public exploit
No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.
Research context
For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.
Timeline
From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.
No dated events beyond publication.
FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).
Patch and commit links
Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.
Credits
All researchersFinders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.
No credits in the CNA record.
Variant candidates
Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.
No nightly-computed relations.
Chain candidates
An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.
—
Bug bounty scope
No known public program.
Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).
Technical details
Attack conditions
- Anyone who can reach it over the internet can trigger it.
- A low-privileged account is enough.
- No user action is required.
- No special conditions are required; it is repeatable.
If successful
- Confidentiality
- low · data can be read
- Integrity
- low · data or configuration can be modified
- Availability
- none
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- Low
- Integrity impact
- Low
- Availability impact
- None
Weakness class (CWE)
CWE-209 · Generation of Error Message Containing Sensitive InformationCVSS vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N
nvd-primary
Attack context
MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.
Change log
- Fix✗ → ✓
For records you follow, these changes also arrive as notifications. →
References
Show all references (2 more)Show less
Vendor advisories and official records. Exploit/PoC links are deliberately left out.