CWE-1286 · Improper Validation of Syntactic Correctness of Input

CWE-1286BaseIncomplete

Abstraction: Base

Status: Incomplete

Improper Validation of Syntactic Correctness of Input

The product receives input that is expected to be well-formed - i.e., to comply with a certain syntax - but it does not validate or incorrectly validates that the input complies with the syntax.

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CVE-2025-41719A low privileged remote attacker can corrupt the webserver users storage on the device by setting a sequence of unsupported characters which leads to deletion of all previously configured users and the creation of the default Administrator with a known default password.

CVE-2021-31988A user controlled parameter related to SMTP test functionality is not correctly validated making it possible to add the Carriage Return and Line Feed (CRLF) control characters and include arbitrary SMTP headers in the generated test email.

CVE-2026-33778An Improper Validation of Syntactic Correctness of Input vulnerability in the IPsec library used by kmd and iked of Juniper Networks Junos OS on SRX Series and MX Series allows an unauthenticated, network-based attacker to cause a complete Denial-of-Service (DoS). If an affected device receives a specifically malformed first ISAKMP packet from the initiator, the kmd/iked process will crash and restart, which momentarily prevents new security associations (SAs) for from being established. Repeated exploitation of this vulnerability causes a complete inability to establish new VPN connections. This issue affects Junos OS on SRX Series and MX Series: * all versions before 22.4R3-S9, * 23.2 version before 23.2R2-S6, * 23.4 version before 23.4R2-S7, * 24.2 versions before 24.2R2-S4, * 24.4 versions before 24.4R2-S3, * 25.2 versions before 25.2R1-S2, 25.2R2.

CVE-2026-21917An Improper Validation of Syntactic Correctness of Input vulnerability in the Web-Filtering module of Juniper Networks Junos OS on SRX Series allows an unauthenticated, network-based attacker to cause a Denial-of-Service (DoS). If an SRX device configured for UTM Web-Filtering receives a specifically malformed SSL packet, this will cause an FPC crash and restart. This issue affects Junos OS on SRX Series: * 23.2 versions from 23.2R2-S2 before 23.2R2-S5, * 23.4 versions from 23.4R2-S1 before 23.4R2-S5, * 24.2 versions before 24.2R2-S2, * 24.4 versions before 24.4R1-S3, 24.4R2. Earlier versions of Junos are also affected, but no fix is available.

CVE-2025-8873On affected platforms running Arista EOS with IPsec configured, a specially crafted packet can cause the dataplane to stop processing all IPsec traffic. The control plane may detect this condition, and attempt to reset the IPsec processing pipeline. After reset traffic may not resume being processed. There is no impact to non-IPsec traffic or to IPsec traffic not originating or terminating on the system. This issue was reported by an Arista customer.

CVE-2025-11573An infinite loop issue in Amazon.IonDotnet library versions <v1.3.2 may allow a threat actor to cause a denial of service through a specially crafted text input. To mitigate this issue, users should upgrade to version v1.3.2. As of August 20, 2025, this library has been deprecated and will not receive further updates.

CVE-2024-39542An Improper Validation of Syntactic Correctness of Input vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on MX Series with MPC10/11 or LC9600, MX304, and Junos OS Evolved on ACX Series and PTX Series allows an unauthenticated, network based attacker to cause a Denial-of-Service (DoS). This issue can occur in two scenarios: 1. If a device, which is configured with SFLOW and ECMP, receives specific valid transit traffic, which is subject to sampling, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. (This scenario is only applicable to PTX but not to ACX or MX.) 2. If a device receives a malformed CFM packet on an interface configured with CFM, the packetio process crashes, which in turn leads to an evo-aftman crash and causes the FPC to stop working until it is restarted. Please note that the CVSS score is for the formally more severe issue 1. The CVSS score for scenario 2. is: 6.5 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) This issue affects Junos OS: * All versions before 21.2R3-S4, * 21.4 versions before 21.4R2, * 22.2 versions before 22.2R3-S2; Junos OS Evolved: * All versions before 21.2R3-S8-EVO, * 21.4 versions before 21.4R2-EVO.

CVE-2026-6442Improper validation of bash commands in Snowflake Cortex Code CLI versions prior to 1.0.25 allowed subsequent commands to execute outside the sandbox. An attacker could exploit this by embedding specially crafted commands in untrusted content, such as a malicious repository, causing the CLI agent to execute arbitrary code on the local device without user consent. Exploitation is non-deterministic and model-dependent. The fix is automatically applied upon relaunch with no user action required.

CVE-2024-0218A Denial of Service (Dos) vulnerability in Nozomi Networks Guardian, caused by improper input validation in certain fields used in the Radius parsing functionality of our IDS, allows an unauthenticated attacker sending specially crafted malformed network packets to cause the IDS module to stop updating nodes, links, and assets. Network traffic may not be analyzed until the IDS module is restarted.

CVE-2023-32649A Denial of Service (Dos) vulnerability in Nozomi Networks Guardian and CMC, due to improper input validation in certain fields used in the Asset Intelligence functionality of our IDS, allows an unauthenticated attacker to crash the IDS module by sending specially crafted malformed network packets. During the (limited) time window before the IDS module is automatically restarted, network traffic may not be analyzed.

CVE-2024-26507An issue in FinalWire AIRDA Extreme, AIDA64 Engineer, AIDA64 Business, AIDA64 Network Audit v.7.00.6700 and before allows a local attacker to escalate privileges via the DeviceIoControl call associated with MmMapIoSpace, IoAllocateMdl, MmBuildMdlForNonPagedPool, or MmMapLockedPages components.

CVE-2026-7307A flaw was found in Keycloak. A remote, unauthenticated attacker can send a specially crafted XML input to the Security Assertion Markup Language (SAML) endpoint. This malicious input can cause high CPU usage and worker thread starvation, leading to a Denial of Service (DoS) where the server becomes unavailable.

CVE-2026-40198Net::CIDR::Lite versions before 0.23 for Perl does not validate IPv6 group count, which may allow IP ACL bypass. _pack_ipv6() does not check that uncompressed IPv6 addresses (without ::) have exactly 8 hex groups. Inputs like "abcd", "1:2:3", or "1:2:3:4:5:6:7" are accepted and produce packed values of wrong length (3, 7, or 15 bytes instead of 17). The packed values are used internally for mask and comparison operations. find() and bin_find() use Perl string comparison (lt/gt) on these values, and comparing strings of different lengths gives wrong results. This can cause find() to incorrectly report an address as inside or outside a range. Example: my $cidr = Net::CIDR::Lite->new("::/8"); $cidr->find("1:2:3"); # invalid input, incorrectly returns true This is the same class of input validation issue as CVE-2021-47154 (IPv4 leading zeros) previously fixed in this module. See also CVE-2026-40199, a related issue in the same function affecting IPv4 mapped IPv6 addresses.

CVE-2025-30415Denial of service due to improper handling of malformed input. The following products are affected: Acronis Cyber Protect Cloud Agent (Linux, macOS, Windows) before build 40077.