CVE-2023-49944

The Challenge Response feature of BeyondTrust Privilege Management for Windows PMfW before 2023-07-14 allows local administrators to bypass this feature by decrypting the shared key, or by locating the decrypted shared key in process memory. The threat is mitigated by the Agent Protection feature...

CVE-2021-41467

Cross-site scripting XSS vulnerability in application/controllers/dropbox.php in JustWriting 1.0.0 and below allow remote attackers to inject arbitrary web script or HTML via the challenge parameter...

CVE-2022-26943

The Motorola MTM5000 series firmwares generate TETRA authentication challenges using a PRNG using a tick count register as its sole entropy source. Low boottime entropy and limited re-seeding of the pool renders the authentication challenge vulnerable to two attacks. First, due to the limited...

Unified Framework for Qualifying Security Boundary of PUFs against Machine Learning Attacks

Physical Unclonable Functions PUFs serve as lightweight, hardware-intrinsic entropy sources widely deployed in IoT security applications. However, delay-based PUFs are vulnerable to Machine Learning Attacks MLAs, undermining their assumed unclonability. There are no valid metrics for evaluating P...

CVE-1999-0391

The cryptographic challenge of SMB authentication in Windows 95 and Windows 98 can be reused, allowing an attacker to replay the response and impersonate a user...

SUSE CVE-2025-68113

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

PT-2025-53609

Name of the Vulnerable Software and Affected Versions FreshRSS versions prior to 1.28.0 Description FreshRSS utilizes weak random number generators mt rand and uniqid for creating remember-me authentication tokens and challenge-response nonces. This allows attackers to predict valid session token...

CVE-2025-62004

BullWall Server Intrusion Protection services are initialized after login services. An authenticated attacker with administrative permissions can log in after boot and bypass MFA. SIP service does not retroactively enforce the challenge or disconnect unauthenticated sessions. Versions 4.6.0.0,...

PT-2025-52342

Name of the Vulnerable Software and Affected Versions BullWall versions 4.6.0.0 through 4.6.1.4 Description BullWall Server Intrusion Protection services start after login services. An attacker who is already authenticated and has administrative privileges can log in following a system boot,...

CVE-2025-68113

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

GO-2025-4239 ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay in github.com/altcha-org/altcha-lib-go

ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay in github.com/altcha-org/altcha-lib-go...

CVE-2025-68113

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

CVE-2025-68113

CVE-2025-68113 (ALTCHA) describes a cryptographic semantic binding flaw in ALTCHA libraries where the HMAC does not unambiguously bind challenge parameters to the nonce, enabling potential replay of previously solved challenges depending on server-side handling. Affected components include ALTCHA...

CVE-2025-68113 ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

EUVD-2025-203484

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

CVE-2025-68113 ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

CVE-2025-68113 ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay

ALTCHA is privacy-first software for captcha and bot protection. A cryptographic semantic binding flaw in ALTCHA libraries allows challenge payload splicing, which may enable replay attacks. The HMAC signature does not unambiguously bind challenge parameters to the nonce, allowing an attacker to...

Improper Verification of Cryptographic Signature

Overview Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature via the HMAC computation. An attacker can bypass intended challenge expiration and reuse previously solved challenges by submitting a valid proof-of-work with a modified expiration value,...

Improper Verification of Cryptographic Signature

Overview Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature via the HMAC computation. An attacker can bypass intended challenge expiration and reuse previously solved challenges by submitting a valid proof-of-work with a modified expiration value,...

Improper Verification of Cryptographic Signature

Overview Affected versions of this package are vulnerable to Improper Verification of Cryptographic Signature via the HMAC computation. An attacker can bypass intended challenge expiration and reuse previously solved challenges by submitting a valid proof-of-work with a modified expiration value,...