CVE-2026-63573 is a high-severity vulnerability in Legion of the Bouncy Castle Inc.'s bc-csharp library before version 2.7.0. It involves an observable discrepancy in the CMS RSA PKCS#1 v1.5 key-transport unwrap process. This discrepancy allows a remote attacker, who can submit many modified CMS EnvelopedData messages to an application using the vulnerable library, to perform a Bleichenbacher-style adaptive chosen-ciphertext attack. The attacker can recover the content-encryption key of a captured message by distinguishing between different error messages during decryption, thus potentially decrypting the message content.
CVE-2026-63572 is a high-severity vulnerability in Legion of the Bouncy Castle Inc.'s bc-csharp library before version 2.7.0. It involves allocation of resources without limits during PKCS#12 keystore loading, allowing an attacker to cause denial of service via CPU exhaustion by supplying a specially crafted PKCS#12 file with a very high iteration count. This iteration count is used in key derivation before password verification, leading to excessive CPU usage. The vulnerability affects the Pkcs12Store.Load method and Pkcs12Utilities.ConvertToDefiniteLength. Versions from 0 up to but not including 2.7.0 are affected.
CVE-2026-63571 is a high-severity vulnerability in Legion of the Bouncy Castle Inc.'s bc-csharp library before version 2.7.0. It involves improper verification of cryptographic signatures in the attribute certificate path validator, allowing a remote attacker to forge X.509 attribute certificates. This flaw permits acceptance of forged certificates that name a trusted attribute authority as issuer but are not actually signed by it. Only applications using these specific classes for attribute certificate validation are affected.
CVE-2026-63570 is a high-severity vulnerability in Legion of the Bouncy Castle Inc.'s bc-csharp library before version 2.7.0. It involves an infinite loop in the Pkcs12Store.GetCertificateChain method when processing crafted PKCS#12 files containing certificate chains with cyclic issuer links. This causes a denial of service by consuming CPU and memory until an OutOfMemoryException occurs.
Allocation of resources without limits or throttling in the CMP/CRMF password-based MAC verifier (PKMacBuilder) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated attacker to cause a denial of service through CPU exhaustion via a CMP message or CRMF certificate request whose PBMParameter declares a very large iteration count, because PKMacBuilder enforced its iteration-count ceiling only when the caller had supplied an explicit maximum through the PKMacBuilder(IPKMacPrimitivesProvider, int) constructor. With any other constructor, ProtectedPkiMessage.Verify and CertificateRequestMessage.IsValidSigningKeyPop performed as many hash iterations as the sender requested, up to about 2^31, before the MAC could be checked.
Observable discrepancy in IesEngine.DecryptBlock in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has captured an IES or ECIES ciphertext, and who can submit modified ciphertexts for decryption under the same key pair, to recover its plaintext via a CBC padding-oracle attack, because in block-cipher mode the engine decrypts the ciphertext and removes its padding before verifying the MAC. A padding failure is therefore reported with a different error message, and without the MAC computation, compared with a MAC failure. Only applications that construct IesEngine directly with a padded block cipher, such as AES in CBC mode with PKCS#7 padding, are affected; stream-mode IES is not.
Memory allocation with excessive size value in the DTLS handshake reassembly (DtlsReliableHandshake, DtlsReassembler) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote unauthenticated DTLS peer to cause a denial of service through memory exhaustion via crafted handshake message fragments, because the reassembly buffer for each incoming handshake message was allocated at the 24-bit length declared in the fragment header, without the check against the peer's maximum handshake message size that TLS already applied. A fragment carrying no payload can force an allocation of almost 16 MB, for each of up to 16 pending messages per handshake, before the handshake is authenticated. DTLS servers and DTLS clients are both affected; TLS is not.
The MStore API WordPress plugin before 4.22.1 does not restrict which fields of an order a customer may update, allowing any authenticated user with a self-registerable account to change the status of their own unpaid order to a paid or fulfilled state and receive the goods without paying.
The Unlimited Elements for Elementor WordPress plugin before 2.0.21 does not check that a request to render widget output comes from a user allowed to make it, allowing users with a role as low as subscriber to have arbitrary WordPress shortcodes executed on the site. Version 2.0.18 removed the subscriber-level access, so from 2.0.18 onward the issue requires a Contributor role or above.
The WebToffee Gift Cards for WooCommerce WordPress plugin before 1.3.1 does not validate a user-supplied gift card amount server-side before using it as the cart-item price and store-credit coupon value, allowing unauthenticated users to submit an arbitrary or negative amount, bypassing the configured denominations and manipulating the order total to obtain products without paying.
The Easy PayPal & Stripe Buy Now Button WordPress plugin before 2.0.6 does not derive the payment amount on the server, taking it from a client-supplied field, so an unauthenticated attacker sets an arbitrary lower price for a purchase.
The WP Edit Password Protected WordPress plugin before 2.0.7 does not enforce its site-wide access restriction on the WordPress REST API, allowing unauthenticated users to read the content of published posts and pages that the site's access mode was configured to hide.
The Popup Maker WP WordPress plugin through 1.4.5 does not perform authorization checks on several of its actions and exposes its management page to any logged-in user, allowing users with a low-privileged role such as Subscriber to store display-targeting values that are later invoked as zero-argument PHP callables on public page loads, leading to sensitive information disclosure and denial of service.
The WP Mail Logging WordPress plugin before 1.17.0 does not properly restrict the HTML and CSS of logged emails before rendering them in its admin log screens, allowing unauthenticated users to inject styled content and links, for example through a public contact form, that can deceive an administrator viewing the log and send their browser to an attacker-controlled page.
The CMP – Coming Soon & Maintenance WordPress plugin before 4.1.20 does not correctly restrict access to the site while maintenance/coming-soon mode is enabled, allowing unauthenticated visitors to bypass the coming-soon page and reach the otherwise hidden site, including hidden published pages, by shaping the request so it is mistaken for a login request.
Exposure of the message authentication key through the encryption keystream in the stream mode of IesEngine (an IesEngine constructed without a block cipher) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows a remote attacker who has observed one encrypted message with known plaintext to forge shorter messages of their choosing that the recipient accepts as authentic, via a crafted ciphertext and MAC tag, because the MAC key was taken from the key derivation output directly after a keystream as long as the message, while the derivation input depends only on the static key pair and fixed parameters. The keystream revealed by that one message therefore contains the MAC key for every sufficiently shorter message.
Missing cryptographic step in the DSTU 7624 CCM mode implementation (KCcmBlockCipher) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an attacker who can observe encrypted messages of known or chosen content to forge ciphertexts with valid authentication tags, via messages encrypted without associated data. The cause is that the G1 block, which binds the nonce, the message length and the parameter flags into the CBC-MAC, was processed only when associated data was present. Without associated data the tag was a CBC-MAC of the plaintext alone, independent of the nonce. Only applications that use KCcmBlockCipher directly and supply no associated data are affected.
Improper validation of integrity check value in the AES-CCM implementation (CcmParameters and CcmBlockCipher) in Legion of the Bouncy Castle Inc. bc-csharp before 2.7.0 allows an on-path attacker to modify CCM-encrypted content without detection via an AlgorithmIdentifier whose CCMParameters declare an authentication tag (aes-ICVlen) of zero or another length outside the RFC 5084 set, because CcmParameters accepted any value and CcmBlockCipher validated the tag length only when encrypting, so decryption compared a zero-length or very short tag. Affected paths include ParameterUtilities.GetCipherParameters, used by CmsEnvelopedData and CmsEnvelopedDataParser for EnvelopedData encrypted with AES-CCM, and any caller passing an unchecked tag length to CcmBlockCipher for decryption.
The BA Book Everything WordPress plugin up to version 1.8.28 contains a stored cross-site scripting (XSS) vulnerability via the 'booking_service_qty' parameter. This vulnerability allows unauthenticated attackers to inject malicious scripts that execute when an administrator or privileged user views the injected order record in the plugin's wp-admin order management area. Exploitation requires the privileged user to open the malicious order record, which is part of the normal order review workflow.
The Request a Quote WordPress plugin versions up to 2.5.6 contains a vulnerability where an unauthenticated AJAX handler does not perform authorization checks. This flaw allows unauthenticated users to access contact records of quote-request submissions, including unpublished records. The vulnerability has a medium severity with a CVSS score of 5.3.