CVE Feed

    Dashboard / CVE / CVE-2021-28834

    CVE-2021-28834

    Kramdown before 2.3.1 does not restrict Rouge formatters to the Rouge::Formatters namespace, and thus arbitrary classes can be instantiated.

    Published:Mar 14, 2021
    Last Modified:Nov 21, 2024
    EPS:Mar 19, 2021
    EPSS Score:0.01496
    CVSS Score:9.8

    Affected Products

    Vendor
    Debian
    Product
    Debian Linux
    Vendor
    Fedoraproject
    Product
    Fedora
    Vendor
    Kramdown Project
    Product
    Kramdown

    Exploits

    https://github.com/gettalong/kramdown/pull/708https://github.com/gettalong/kramdown/pull/708

    Common Attack Pattern Enumeration and Classification (CAPEC)

    CAPEC-138 Reflection Injection

    Related CVEs

    CVE-2026-77118 (CVSS 8.4) — A heap out-of-bounds write exists in the Photo CD (PCD) decoder of GraphicsMagick. In DecodeImage() (coders/pc…
    CVE-2026-56968 (CVSS 3.7) — GNU SASL before 2.2.4 lacks sanitization of a short challenge in _gsasl_ntlm_client_step in the NTLM client, w…
    CVE-2026-49975 (CVSS 7.5) — Memory Allocation with Excessive Size Value vulnerability in Apache HTTP Server's mod_http leads to denial of …
    CVE-2026-9256 (CVSS 9.2) — NGINX Plus and NGINX Open Source have a vulnerability in the ngx_http_rewrite_module module. This vulnerabilit…
    CVE-2026-31431 (CVSS 7.8) — In the Linux kernel, the following vulnerability has been resolved: crypto: algif_aead - Revert to operating …
    CVE-2026-34757 (CVSS 5.1) — LIBPNG is a reference library for use in applications that read, create, and manipulate PNG (Portable Network …
    CVE-2026-4775 (CVSS 7.8) — A flaw was found in the libtiff library. A remote attacker could exploit a signed integer overflow vulnerabili…
    CVE-2025-63261 (CVSS 7.8) — AWStats 8.0 is vulnerable to Command Injection via the open function…
    CVE-2026-3497 (CVSS 6.9) — Vulnerability in the OpenSSH GSSAPI delta included in various Linux distributions. This vulnerability affects …
    CVE-2026-1940 (CVSS 5.1) — An incomplete fix for CVE-2024-47778 allows an out-of-bounds read in gst_wavparse_adtl_chunk() function. The p…

    References

    https://github.com/gettalong/kramdown/compare/REL_2_3_0...REL_2_3_1
    https://github.com/gettalong/kramdown/pull/708
    https://gitlab.com/gitlab-org/gitlab/-/commit/179329b5c3c118924fb242dc449d06b4ed6ccb66
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NJCJVYHPY6LNUFM6LYZIAUIYOMVT5QGV/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S3BBLUIDCUUR3NEE4NJLOCCAV3ALQ3O6/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SYOLQKFL6IJCQLBXV34Z4TI4O54GESPR/
    https://www.debian.org/security/2021/dsa-4890
    https://github.com/gettalong/kramdown/compare/REL_2_3_0...REL_2_3_1
    https://github.com/gettalong/kramdown/pull/708
    https://gitlab.com/gitlab-org/gitlab/-/commit/179329b5c3c118924fb242dc449d06b4ed6ccb66
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/NJCJVYHPY6LNUFM6LYZIAUIYOMVT5QGV/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/S3BBLUIDCUUR3NEE4NJLOCCAV3ALQ3O6/
    https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/SYOLQKFL6IJCQLBXV34Z4TI4O54GESPR/
    https://www.debian.org/security/2021/dsa-4890

    Common Vulnerability Scoring System

    Attack Vector
    Network
    Adjacent
    Local
    Physical
    Privileges Required
    None
    Low
    High
    User Interaction
    None
    Required
    Scope
    Unchanged
    Changed
    Confidentiality
    None
    Low
    High
    Integrity
    None
    Low
    High
    Availability
    None
    Low
    High