Malicious PDF — malware analysis report

Static analysis result for SHA-256 73f6d5e9f105c4f2…

MALICIOUS

PDF

32.1 KB Created: 2020-08-19 22:47:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e24dfa23cadb86720655e69c55f74ff8 SHA-1: 77a762874bdf66a53b669f91d475d050580d3893 SHA-256: 73f6d5e9f105c4f23d515ab35a0146bc77560849cca0bdfa01e4d426ea6212dd
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded links, with one identified as a malicious redirector. The ML classifier strongly flagged this PDF as malicious, and the presence of a link farm suggests an attempt to manipulate search engine results or direct users to malicious content. The document body itself is heavily obfuscated and contains the malicious URL.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.ru/pify?keyword=reported+speech+exercises+mixed+types+pdf
    • http://vakaj.eleven1church.com/uploads/1/3/0/7/130738894/sexodewotam_vugibeka_wasinogosup_vobit.pdf
    • http://dejuxota.cchpcharleswood.org/uploads/1/3/0/8/130814124/xukevoti.pdf
    • http://files.northportcarpet.com/uploads/1/3/1/3/131382078/2db4601.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0432/1512/6692/files/15478477074.pdf
    • https://cdn.shopify.com/s/files/1/0434/3644/1767/files/cells_alive_webquest_answer_key.pdf
    • https://cdn.shopify.com/s/files/1/0433/7644/3543/files/5050843919.pdf
    • https://cdn.shopify.com/s/files/1/0428/3393/6547/files/nedujuwopu.pdf
    • https://cdn.shopify.com/s/files/1/0429/7624/7971/files/34597157031.pdf
    • https://cdn.shopify.com/s/files/1/0438/4486/2114/files/vunojolomusigumewemibawa.pdf
    • https://cdn.shopify.com/s/files/1/0432/3724/5085/files/assessment_of_teaching_assistant_skills.pdf
    • https://cdn.shopify.com/s/files/1/0432/2859/4336/files/belajar_bahasa_jepang_apk_pro.pdf
    • https://cdn.shopify.com/s/files/1/0435/4031/6319/files/nopote.pdf
    • https://cdn.shopify.com/s/files/1/0433/9423/6572/files/vazefikulipobi.pdf
    • https://cdn.shopify.com/s/files/1/0428/5123/8047/files/pdf_to_word_converter_download_adobe.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000040d3.bin
5abd68815d2dd5c9f2a546a0cce456bc0c8f6153155fe65bfbdd652b46f512de
pdf-font-stream PDF embedded font (sfnt) at offset 0x40D3 5332 bytes
font_01_sfnt_off000052e7.bin
99945bcb436f086bc0b6040fca2327ac009770e057cebb13b27cd0307a8eb7ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x52E7 9672 bytes