CVE-2025-68113
MediumCVSS 6.5Exploitation Probability (EPSS)
Low risk38th percentile - higher than 38% of all known CVEs
Summary
ALTCHA libraries contain a cryptographic semantic binding flaw that allows challenge payload splicing, potentially enabling 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 expiration value. This may allow previously solved challenges to be reused beyond their intended lifetime. The issue has been addressed by enforcing explicit semantic separation between challenge parameters and the nonce during HMAC computation.
Risk Assessment
The vulnerability weakens abuse-prevention mechanisms such as rate limiting and bot mitigation, as solved challenges may be replayed beyond their intended lifetime. It does not directly affect data confidentiality or integrity.
Recommendation
Upgrade ALTCHA libraries to patched versions (including altcha Golang 1.0.0, altcha Rubygem 1.0.0, altcha pip 1.0.0, altcha Erlang 1.0.0, altcha-lib npm 1.4.1, altcha-org/altcha Composer 1.3.1, org.altcha:altcha Maven 1.3.0). As a mitigation, append a delimiter to the end of the salt value before HMAC computation (e.g., `<salt>?expires=<time>&`).
Related vulnerabilities
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A security vulnerability has been detected in TOTOLINK CA300-PoE 6.2c.884. The function setWiFiWdsAddConfig in the file /cgi-bin/cstecgi.cgi is affected, where manipulation of the ApCliKeyStr argument leads to a buffer overflow. The attack may be initiated remotely, and the exploit has been disclosed publicly and may be used.
- CVE-2026-124058Critical
A weakness has been identified in TOTOLINK CA300-PoE 6.2c.884. The function setWiFiRepeaterConfig in the file /cgi-bin/cstecgi.cgi is affected, where manipulation of the ApCliKeyStr argument can lead to a buffer overflow. The attack can be launched remotely, and the exploit has been made available to the public and could be used for attacks.
- CVE-2026-124057Critical
A security flaw has been discovered in TOTOLINK CA300-PoE 6.2c.884. This impacts the function setWiFiMultipleConfig of the file /cgi-bin/cstecgi.cgi. Manipulation of the argument Key1Str1 results in a buffer overflow. The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks.
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- CVE-2026-122041Critical
The Checkout Field Editor for WooCommerce (Pro) plugin for WordPress up to and including 3.8.0 is vulnerable to unauthorized deletion of arbitrary attachments due to a missing capability/ownership check in the ajax_remove_uploaded() function. The handler is registered for both wp_ajax and wp_ajax_nopriv and gated solely by the 'file_handling_nonce' nonce, which is exposed in the public checkout page markup.
- CVE-2026-119075Critical
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The LatePoint plugin for WordPress is vulnerable to authentication bypass via account takeover in versions up to and including 5.7.6. OsModel::build_conditions_query() compares WHERE-clause values against literal strings 'IS NULL' and 'IS NOT NULL' and concatenates a match directly into SQL without binding, allowing unauthenticated attackers to send params[password_reset_token]=IS NOT NULL to the public customer_cabinet__change_password AJAX route and overwrite the lowest-id customer's password.
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The Naimur Email OTP Verification for WooCommerce plugin is vulnerable to authentication bypass in versions up to and including 2.1.0. The password-reset finalization endpoint authorizes the reset solely by the presence of a database row marking an email as 'VERIFIED', with no timestamp check, session binding, or per-reset token, and the scheduled cleanup cron has no handler so it never runs.
- CVE-2026-123961Critical
A vulnerability was detected in TOTOLINK CA300-PoE version 6.2c.884 affecting the setWiFiBasicConfig function in /cgi-bin/cstecgi.cgi. Manipulation of the KeyStr argument leads to a buffer overflow. The attack can be initiated remotely and a public exploit is available.
Original NVD description (English source)
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 reinterpret a valid proof-of-work submission with a modified expiration value. This may allow previously solved challenges to be reused beyond their intended lifetime, depending on server-side replay handling and deployment assumptions. The vulnerability primarily impacts abuse-prevention mechanisms such as rate limiting and bot mitigation. It does not directly affect data confidentiality or integrity. This issue has been addressed by enforcing explicit semantic separation between challenge parameters and the nonce during HMAC computation. Users are advised to upgrade to patched versions, which include version 1.0.0 of the altcha Golang package, version 1.0.0 of the altcha Rubygem, version 1.0.0 of the altcha pip package, version 1.0.0 of the altcha Erlang package, version 1.4.1 of the altcha-lib npm package, version 1.3.1 of the altcha-org/altcha Composer package, and version 1.3.0 of the org.altcha:altcha Maven package. As a mitigation, implementations may append a delimiter to the end of the `salt` value prior to HMAC computation (for example, `<salt>?expires=<time>&`). This prevents ambiguity between parameters and the nonce and is backward-compatible with existing implementations, as the delimiter is treated as a standard URL parameter separator.
Vulnerability data from NVD (NIST) · CISA KEV · EPSS

