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Weakness (CWE)

CWE-76: Improper Neutralization of Equivalent Special Elements

Base Draft

The product correctly neutralizes certain special elements, but it improperly neutralizes equivalent special elements.

More detail

The product may have a fixed list of special characters it believes is complete. However, there may be alternate encodings, or representations that also have the same meaning. For example, the product may filter out a leading slash (/) to prevent absolute path names, but does not account for a tilde (~) followed by a user name, which on some *nix systems could be expanded to an absolute pathname. Alternately, the product might filter a dangerous "-e" command-line switch when calling an external program, but it might not account for "--exec" or other switches that have the same semantics.

How to prevent it (2 mitigations)

  1. Requirements

    Programming languages and supporting technologies might be chosen which are not subject to these issues.

  2. Implementation

    Utilize an appropriate mix of allowlist and denylist parsing to filter equivalent special element syntax from all input.

Source: MITRE CWE-76

All Critical High Medium Low Exploited only Public exploit

4 results · Clear filters · Feed

  • Medium 6.3
    CVE-2024-1883 EPSS 61%

    Reflected XSS in PaperCut NG/MF

    This is a reflected cross site scripting vulnerability in the PaperCut NG/MF application server. An attacker can exploit this weakness by crafting a malicious URL that contains a script. When an unsuspecting user clicks on this malicious link, it could potent…

    PaperCut PaperCut NG, PaperCut MF
  • Medium 6.5
    CVE-2024-21600

    Junos OS: PTX Series: In an FTI scenario MPLS packets hitting reject next-hop will cause a host path wedge condition

    An Improper Neutralization of Equivalent Special Elements vulnerability in the Packet Forwarding Engine (PFE) of Juniper Networks Junos OS on PTX Series allows a unauthenticated, adjacent attacker to cause a Denial of Service (DoS). When MPLS packets are mean…

    Juniper Networks Junos OS Network devices
  • Medium 5.7
    CVE-2023-1149

    Improper Neutralization of Equivalent Special Elements in btcpayserver/btcpayserver

    Improper Neutralization of Equivalent Special Elements in GitHub repository btcpayserver/btcpayserver prior to 1.8.0.

    btcpayserver btcpayserver/btcpayserver
  • Medium 5.3
    CVE-2023-0493 Public exploit

    Improper Neutralization of Equivalent Special Elements in btcpayserver/btcpayserver

    Improper Neutralization of Equivalent Special Elements in GitHub repository btcpayserver/btcpayserver prior to 1.7.5.

    btcpayserver btcpayserver/btcpayserver