1556 matches found
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...
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...
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
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...
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,...
ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay
Impact 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 reinterpret a valid proof-of-work submission with a modifi...
GHSA-6GVQ-JCMP-8959 ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay
Impact 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 reinterpret a valid proof-of-work submission with a modifi...
Improper Verification of Cryptographic Signature
Overview altcha is an A lightweight library for creating and verifying ALTCHA challenges. 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...
PT-2025-54688
Impact 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 reinterpret a valid proof-of-work submission with a modifi...
PT-2025-51359
Name of the Vulnerable Software and Affected Versions ALTCHA versions prior to 1.0.0 Golang package ALTCHA versions prior to 1.0.0 Rubygem package ALTCHA versions prior to 1.0.0 pip package ALTCHA versions prior to 1.0.0 Erlang package ALTCHA versions prior to 1.4.1 altcha-lib npm package ALTCHA...
PT-2025-54735
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
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 reinterpret a valid proof-of-work submission with a modified...
ALTCHA data falsification vulnerability
ALTCHA is a self-hosted CAPTCHA software from ALTCHA Open Source. ALTCHA suffers from a Data Forgery Problem vulnerability that stems from HMAC signatures not explicitly bound to challenge parameters, which could lead to replay attacks...
ALTCHA Proof-of-Work Vulnerable to Challenge Splicing and Replay
Impact 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 reinterpret a valid proof-of-work submission with a modifi...
