Weakness (CWE)
CWE-203: Observable Discrepancy
The product behaves differently or sends different responses under different circumstances in a way that is observable to an unauthorized actor.
How to prevent it (2 mitigations)
-
Architecture and Design
Compartmentalize the system to have "safe" areas where trust boundaries can be unambiguously drawn. Do not allow sensitive data to go outside of the trust boundary and always be careful when interfacing with a compartment outside of the safe area.
Ensure that appropriate compartmentalization is built into the system design, and the compartmentalization allows for and reinforces privilege separation functionality. Architects and designers should rely on the principle of least privilege to decide the appropriate time to use privileges and the time to drop privileges.
-
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.
Source: MITRE CWE-203
461 results · Feed
-
Medium 5.3CVE-2016-20012 Public exploit
OpenSSH through 8.7 allows remote attackers, who have a suspicion that a certain combination of username and public key…
-
Medium 5.3
Observable Response Discrepancy in Lost Password Service
Pimcore is an open source data & experience management platform. In versions prior to 10.1.3, it is possible to enumerate usernames via the forgot password functionality. This issue is fixed in version 10.1.3. As a workaround, one may apply the available patc…
-
Medium 5.3
Observable Discrepancy in Wildfly Elytron
A flaw was found in Wildfly Elytron in versions prior to 1.10.14.Final, prior to 1.15.5.Final and prior to 1.16.1.Final where ScramServer may be susceptible to Timing Attack if enabled. The highest threat of this vulnerability is confidentiality.
-
High 7.5
Information Exposure in mymbCONNECT24, mbCONNECT24 <= 2.8.0
In MB connect line mymbCONNECT24, mbCONNECT24 in versions <= 2.8.0 an unauthenticated user can enumerate valid users by checking what kind of response the server sends.
-
Medium 5.3
An issue was discovered in Arm Mbed TLS before 2.23.0. Because of a side channel in modular exponentiation, an RSA priv…
-
Medium 5.3
Observable Response Discrepancy in Flask-AppBuilder
Flask-AppBuilder is a development framework, built on top of Flask. User enumeration in database authentication in Flask-AppBuilder <= 3.2.3. Allows for a non authenticated user to enumerate existing accounts by timing the response time from the server when y…
-
Medium 5.9
Observable Timing Discrepancy in aaugustin websockets library
The aaugustin websockets library before 9.1 for Python has an Observable Timing Discrepancy on servers when HTTP Basic Authentication is enabled with basic_auth_protocol_factory(credentials=...). An attacker may be able to guess a password via a timing attack.
-
Medium 5.1
Timing based private key exposure in Bouncy Castle
Bouncy Castle BC Java before 1.66, BC C# .NET before 1.8.7, BC-FJA before 1.0.1.2, 1.0.2.1, and BC-FNA before 1.0.1.1 have a timing issue within the EC math library that can expose information about the private key when an attacker is able to observe timing i…
-
Medium 5.3CVE-2021-21424 Public exploit
Prevent user enumeration using Guard or the new Authenticator-based Security
Symfony is a PHP framework for web and console applications and a set of reusable PHP components. The ability to enumerate users was possible without relevant permissions due to different handling depending on whether the user existed or not when attempting t…
-
Medium 5.3
Cisco SD-WAN vManage HTTP Authentication User Enumeration Vulnerability
A vulnerability in Cisco SD-WAN vManage Software could allow an unauthenticated, remote attacker to enumerate user accounts. This vulnerability is due to the improper handling of HTTP headers. An attacker could exploit this vulnerability by sending authentica…
-
Medium 4.0
Timing side channel vulnerability in UIDL request handler in Vaadin 7 and 8
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:vaadin-server versions 7.0.0 through 7.7.23 (Vaadin 7.0.0 through 7.7.23), and 8.0.0 through 8.12.2 (Vaadin 8.0.0 through 8.12.2) allows attacker to guess a security token via t…
-
Medium 4.0
Timing side channel vulnerability in UIDL request handler in Vaadin 10, 11-14, and 15-18
Non-constant-time comparison of CSRF tokens in UIDL request handler in com.vaadin:flow-server versions 1.0.0 through 1.0.13 (Vaadin 10.0.0 through 10.0.16), 1.1.0 prior to 2.0.0 (Vaadin 11 prior to 14), 2.0.0 through 2.4.6 (Vaadin 14.0.0 through 14.4.6), 3.0.…
-
Medium 4.0
Timing side channel vulnerability in endpoint request handler in Vaadin 15-19
Non-constant-time comparison of CSRF tokens in endpoint request handler in com.vaadin:flow-server versions 3.0.0 through 5.0.3 (Vaadin 15.0.0 through 18.0.6), and com.vaadin:fusion-endpoint version 6.0.0 (Vaadin 19.0.0) allows attacker to guess a security tok…
-
Medium 5.9
Padding Oracle Attack due to Observable Timing Discrepancy in jose-node-cjs-runtime
jose-node-cjs-runtime is an npm package which provides a number of cryptographic functions. In versions prior to 3.11.4 the AES_CBC_HMAC_SHA2 Algorithm (A128CBC-HS256, A192CBC-HS384, A256CBC-HS512) decryption would always execute both HMAC tag verification an…
-
Medium 5.9
Padding Oracle Attack due to Observable Timing Discrepancy in jose-node-esm-runtime
jose-node-esm-runtime is an npm package which provides a number of cryptographic functions. In versions prior to 3.11.4 the AES_CBC_HMAC_SHA2 Algorithm (A128CBC-HS256, A192CBC-HS384, A256CBC-HS512) decryption would always execute both HMAC tag verification an…
-
Medium 5.9
Padding Oracle Attack due to Observable Timing Discrepancy in jose-browser-runtime
jose-browser-runtime is an npm package which provides a number of cryptographic functions. In versions prior to 3.11.4 the AES_CBC_HMAC_SHA2 Algorithm (A128CBC-HS256, A192CBC-HS384, A256CBC-HS512) decryption would always execute both HMAC tag verification and…
-
Medium 5.9
Padding Oracle Attack due to Observable Timing Discrepancy in jose
jose is an npm library providing a number of cryptographic operations. In vulnerable versions AES_CBC_HMAC_SHA2 Algorithm (A128CBC-HS256, A192CBC-HS384, A256CBC-HS512) decryption would always execute both HMAC tag verification and CBC decryption, if either fa…
-
Medium 5.9
Timing attack in Cookie signature verification
Apache Hive cookie signature verification used a non constant time comparison which is known to be vulnerable to timing attacks. This could allow recovery of another users cookie signature. The issue was addressed in Apache Hive 2.3.8
-
High —
/user/sessions endpoint allows detecting valid accounts
This Security Advisory is about a vulnerability in eZ Platform v1.13, v2.5, and v3.2, and in Ibexa DXP and Ibexa Open Source v3.3. The /user/sessions endpoint can let an attacker detect if a given username or email refers to a valid account. This can be detec…
-
Medium 5.3
Observable Differences in Behavior to Error Inputs in Bouncy Castle
In Legion of the Bouncy Castle BC before 1.61 and BC-FJA before 1.0.1.2, attackers can obtain sensitive information about a private exponent because of Observable Differences in Behavior to Error Inputs. This occurs in org.bouncycastle.crypto.encodings.OAEPEn…
-
Medium 5.3
Cisco Firepower 1000 Series Bleichenbacher Attack Vulnerability
A vulnerability in the TLS handler of Cisco Adaptive Security Appliance (ASA) Software and Cisco Firepower Threat Defense (FTD) Software for Cisco Firepower 1000 Series firewalls could allow an unauthenticated, remote attacker to gain access to sensitive info…
-
Medium 5.8
Junos OS: EX4600, QFX5K Series: Stateless firewall filter matching 'user-vlan-id' will cause incomplete discard action
When configuring stateless firewall filters in Juniper Networks EX4600 and QFX 5000 Series devices using Virtual Extensible LAN protocol (VXLAN), the discard action will fail to discard traffic under certain conditions. Given a firewall filter configuration s…
-
Unscored —
SonicOS SSLVPN login page allows a remote unauthenticated attacker to perform firewall management administrator usernam…
-
Medium 5.9
Timing attack in Shrine
In Shrine before version 3.3.0, when using the `derivation_endpoint` plugin, it's possible for the attacker to use a timing attack to guess the signature of the derivation URL. The problem has been fixed by comparing sent and calculated signature in constant …
-
Low 3.7
Raccoon attack
The Raccoon attack exploits a flaw in the TLS specification which can lead to an attacker being able to compute the pre-master secret in connections which have used a Diffie-Hellman (DH) based ciphersuite. In such a case this would result in the attacker bein…
-
High 8.0
Observable Timing Discrepancy in OpenMage LTS
OpenMage LTS before versions 19.4.6 and 20.0.2 allows attackers to circumvent the `fromkey protection` in the Admin Interface and increases the attack surface for Cross Site Request Forgery attacks. This issue is related to Adobe's CVE-2020-9690. It is patche…
-
Medium 4.2
Magento observable timing discrepancy vulnerability
Magento versions 2.3.5-p1 and earlier, and 2.3.5-p1 and earlier have an observable timing discrepancy vulnerability. Successful exploitation could lead to signature verification bypass.
-
Medium 5.5
A flaw was found in the fix for CVE-2019-11135, in the Linux upstream kernel versions before 5.5 where, the way Intel C…
-
Medium 5.9
The client side in OpenSSH 5.7 through 8.4 has an Observable Discrepancy leading to an information leak in the algorith…
-
High 7.2
Magento Signature verification bypass
Magento versions 2.3.4 and earlier, 2.2.11 and earlier (see note), 1.14.4.4 and earlier, and 1.9.4.4 and earlier have an observable timing discrepancy vulnerability. Successful exploitation could lead to signature verification bypass.
-
Low 3.7
Observable Response Discrepancy in TYPO3 CMS
In TYPO3 CMS versions 10.4.0 and 10.4.1, it has been discovered that time-based attacks can be used with the password reset functionality for backend users. This allows an attacker to mount user enumeration based on email addresses assigned to backend user ac…
-
Medium 5.3
Observable Discrepancy in Argo
Fixed in v1.5.1, Argo version v1.5.0 was vulnerable to a user-enumeration vulnerability which allowed attackers to determine the usernames of valid (non-SSO) accounts because /api/v1/session returned 401 for an existing username and 404 otherwise.
-
Medium 5.3
Non-constant time HMAC comparison
Jenkins 2.218 and earlier, LTS 2.204.1 and earlier used a non-constant time comparison function when validating an HMAC.
-
Medium 5.3
Non-constant time comparison of inbound TCP agent connection secret
Jenkins 2.218 and earlier, LTS 2.204.1 and earlier did not use a constant-time comparison function for validating connection secrets, which could potentially allow an attacker to use a timing attack to obtain this secret.
-
Medium 6.5
Tornado XSRF cookie allows side-channel attack against TLS (BREACH attack)
Tornado before 3.2.2 sends arbitrary responses that contain a fixed CSRF token and may be sent with HTTP compression, which makes it easier for remote attackers to conduct a BREACH attack and determine this token via a series of crafted requests.
-
Medium 5.9
Observable Discrepancy in libsecp256k1-rs
A timing vulnerability in the Scalar::check_overflow function in Parity libsecp256k1-rs before 0.3.1 potentially allows an attacker to leak information via a side-channel attack.
-
Medium 6.3
Possible Information Leak / Session Hijack Vulnerability in Rack
There's a possible information leak / session hijack vulnerability in Rack (RubyGem rack). This vulnerability is patched in versions 1.6.12 and 2.0.8. Attackers may be able to find and hijack sessions by using timing attacks targeting the session id. Session …
-
High 8.1
Symfony Http-Kernel has non-constant time comparison in UriSigner
An issue was discovered in Symfony 2.8.0 through 2.8.50, 3.4.0 through 3.4.34, 4.2.0 through 4.2.11, and 4.3.0 through 4.3.7. The UriSigner was subject to timing attacks. This is related to symfony/http-kernel.
-
Medium 5.3
User enumeration leak using switch user functionality in Symfony
An issue was discovered in Symfony 4.2.0 to 4.2.11 and 4.3.0 to 4.3.7. The ability to enumerate users was possible due to different handling depending on whether the user existed when making unauthorized attempts to use the switch users functionality. This is…
-
High 7.4
Timing attacks might allow practical recovery of the long-term private key
In elliptic-php versions priot to 1.0.6, Timing attacks might be possible which can result in practical recovery of the long-term private key generated by the library under certain conditions. Leakage of a bit-length of the scalar during scalar multiplication…