GHSA-m884-279h-32v2 BIT-symfony-2020-5274 CVE-2020-5274
Exceptions displayed in non-debug configurations in Symfony
- Severity
- 4.6 / 10
- Medium · CVSS 3.1
- Exploit chance (EPSS)
- 1.20%
- Chance of exploitation in the next 30 days. Higher than 68.11% of scored vulnerabilities.
- Known exploited
- No
- Not in CISA's catalog
- Weakness
- CWE-209 Generation of Error Message Containing Sensitive Information
- Fix
- Available
- 2 packages have a fixed version
Description
Description
When ErrorHandler renders an exception HTML page, it uses un-escaped properties from the related Exception class to render the stacktrace. The security issue comes from the fact that the stacktraces were also displayed in non-debug environments.
Resolution
The ErrorHandler class now escapes all properties coming from the related Exception, and the stacktrace is not displayed anymore in non-debug environments.
The patches for this issue are available here and here for branch 4.4.
Credits
I would like to thank Luka Sikic for reporting & Yonel Ceruto and Jérémy Derussé for fixing the issue.
Affected versions
Packagist
| Package | Vulnerable | Fixed in |
|---|---|---|
| symfony/error-handler | >= 4.4.0, < 4.4.4 |
4.4.4 |
| symfony/error-handler | >= 5.0.0, < 5.0.4 |
5.0.4 |
| symfony/symfony | >= 4.4.0, < 4.4.4 |
4.4.4 |
| symfony/symfony | >= 5.0.0, < 5.0.4 |
5.0.4 |
How to fix
Move to the fixed version or later with your package manager, update the lockfile, and run your tests. If the package only arrives through another dependency, upgrade that dependency first. If none of its releases pulls a fixed version yet, force the version with your package manager's override.
symfony/error-handler Packagist → 4.4.4
- composer
composer require symfony/error-handler:^4.4.4
symfony/symfony Packagist → 4.4.4
- composer
composer require symfony/symfony:^4.4.4
Severity breakdown
CVSS 3.1 4.6
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- Low
- User interaction
- Required
- Scope
- Unchanged
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Weakness
CWE-209: Generation of Error Message Containing Sensitive Information
The product generates an error message that includes sensitive information about its environment, users, or associated data.
How to prevent it
- Implementation: Ensure that error messages only contain minimal details that are useful to the intended audience and no one else. The messages need to strike the balance between being too cryptic (which can confuse users) or being too detailed (which may reveal more than intended). The messages should not reveal the methods that were used to determine the error. Attackers can use detailed information to refine or optimize their original attack, thereby increasing their chances of success. If errors must be captured in some detail, record them in log messages, but consider what could occur if the log messages can be viewed by attackers. Highly sensitive information such as passwords should never be saved to log files. Avoid inconsistent messaging that might accidentally tip off an attacker about internal state, such as whether a user account exists or not.
- Implementation: Handle exceptions internally and do not display errors containing potentially sensitive information to a user.
- Implementation: Use naming conventions and strong types to make it easier to spot when sensitive data is being used. When creating structures, objects, or other complex entities, separate the sensitive and non-sensitive data as much as possible.
- Implementation, Build and Compilation: Debugging information should not make its way into a production release.
- Implementation, Build and Compilation: Debugging information should not make its way into a production release.
- System Configuration: Where available, configure the environment to use less verbose error messages. For example, in PHP, disable the display_errors setting during configuration, or at runtime using the error_reporting() function.
- System Configuration: Create default error pages or messages that do not leak any information.
References
Advisories
Other links
- github.com/symfony/symfony/security/advisories/GHSA-m884-279h-32v2
- github.com/symfony/symfony/commit/629d21b800a15dc649fb0ae9ed7cd9211e7e45db
- github.com/symfony/symfony/commit/cf80224589ac05402d4f72f5ddf80900ec94d5ad
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/error-handler/C…
- github.com/FriendsOfPHP/security-advisories/blob/master/symfony/symfony/CVE-202…
- symfony.com/cve-2020-5274
Timeline
- Published
- Last updated by the source
- Latest EPSS score
Related advisories
| Advisory | Severity | Why it's related |
|---|---|---|
| GHSA-2v3c-qxhr-7vpv Symfony: Unbounded Recursion in the YAML Inline Lexer Lets a Single Document Crash the Process | High | Also affects symfony/symfony |
| GHSA-r925-mgvr-h9cc Symfony: ReDoS in HeaderUtils::split() Reachable Through the Cache-Control Request Header | High | Also affects symfony/symfony |
| GHSA-h5x3-xfc9-m39h Symfony: UrlGenerator Dot-Segment Encoding Skips Every Other Chained `../` or `./` → Generated URL Collapses Off-Route Under RFC 3986 Normalization | Medium | Also affects symfony/symfony |
| GHSA-v3wm-qf9p-c549 Symfony: HtmlSanitizer URL Parser Deny Gates Underinclusive: Percent-Encoded BiDi Marks and Unicode Whitespace Bypass Visual-Spoofing Defense | Medium | Also affects symfony/symfony |
| GHSA-rrj9-5q2j-4gvr Symfony: Mailomat Mailer Webhook Parser Reads the HMAC Algorithm from the Request: Signature Algorithm Downgrade | Medium | Also affects symfony/symfony |
| GHSA-38cx-cq6f-5755 Symfony: IpUtils::PRIVATE_SUBNETS Omits IPv6 Transition Forms (6to4, NAT64, Teredo, IPv4-compatible): SSRF Bypass in NoPrivateNetworkHttpClient | High | Also affects symfony/symfony |
| GHSA-6h46-9jf5-q59x Symfony: Security Firewall Bypass via failure_forward Subrequest: Unauthenticated Access to access_control-Protected GET Routes | High | Also affects symfony/symfony |
| GHSA-x5qj-865h-mgvm Symfony: HtmlSanitizer UrlAttributeSanitizer Misses URL Attributes | Medium | Also affects symfony/symfony |
MergeHarbor checks every repository's dependencies against this database, ranks what matters by exploitability and reachability, routes it to the owning team and opens the fix pull request.
Check your repos with MergeHarbor