Malicious PDF — malware analysis report

Static analysis result for SHA-256 85f26ef4106c397c…

MALICIOUS

PDF

39.1 KB Created: 2020-08-28 07:11:35 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1d1cd324aebc5edfbffb194deb111cfc SHA-1: 362966c34264157aa76aab45532889632070c5e9 SHA-256: 85f26ef4106c397c5a275c9f435a9117a7515d21e2219fdf95768e156945f47d
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to benign Shopify domains, but one critical link redirects to a known malicious domain. This suggests a link farm or SEO poisoning tactic designed to drive traffic to malicious infrastructure. The ML classifier also strongly indicated maliciousness.

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=sentence+combining+worksheet+high+school+answers
    • http://tesug.acanthusfloral.ca/uploads/1/3/0/7/130738970/6416319.pdf
    • http://files.authoraprilkelley.com/uploads/1/3/2/6/132695491/negekuguruxetu_rajala.pdf
    • http://files.glenoakscommunity.org/uploads/1/3/0/8/130815115/6586241.pdf
    • http://files.justoneopportunity.org/uploads/1/3/0/8/130873902/6899363.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0465/1633/8838/files/adverbs_of_frequency_esl.pdf
    • https://cdn.shopify.com/s/files/1/0431/6640/0673/files/kedidegubufanuzuli.pdf
    • https://cdn.shopify.com/s/files/1/0436/2184/3106/files/ninovakogeropajomejobotan.pdf
    • https://cdn.shopify.com/s/files/1/0428/7424/1183/files/lokusigunusidoza.pdf
    • https://cdn.shopify.com/s/files/1/0428/1620/9059/files/operasi_pada_bilangan_real.pdf
    • https://cdn.shopify.com/s/files/1/0437/5710/9399/files/23468074637.pdf
    • https://cdn.shopify.com/s/files/1/0432/2341/6995/files/the_little_book_of_economics.pdf
    • https://cdn.shopify.com/s/files/1/0433/7978/5886/files/gwent_playing_innkeeps.pdf
    • https://cdn.shopify.com/s/files/1/0430/6521/3089/files/63183715083.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/fejatomamegebuwugibuvu.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_off0000597a.bin
80d75fc38308db8733a4ae9de47fdc0edcf20fc12f221fcbaf420d1c12a7cf9f
pdf-font-stream PDF embedded font (sfnt) at offset 0x597A 5612 bytes
font_01_sfnt_off00006c74.bin
e2a4b14f332ac47b181ad57cfe6fd2ca7a0cc84d7d2c06e4fa4421c1e3e65149
pdf-font-stream PDF embedded font (sfnt) at offset 0x6C74 10088 bytes