Malicious PDF — malware analysis report

Static analysis result for SHA-256 1c920171830afeb1…

MALICIOUS

PDF

34.3 KB Created: 2020-08-16 01:58:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: c5aebf7739c06346f50432db58255c88 SHA-1: 5f3372b08a6f5a9586ae956e286f27ec624cbade SHA-256: 1c920171830afeb1e295cdf21f268af366df3fbbfaa83a291ccaa2b0bd5813c4
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell T1204.002 Malicious Link

The PDF contains embedded links, with one pointing to a known malicious redirector infrastructure at 'ttraff.ru'. The document body, though heavily obfuscated, contains text suggesting it is a 'supervisor's portable answer book pdf', likely a lure. The PDF also hosts a large number of external links, many hosted on Shopify, which is characteristic of SEO link farm abuse to improve search engine ranking for malicious content. The ML classifier 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/wb?keyword=supervisor
    • http://kodojik.newbethelrolesville.com/uploads/1/3/1/6/131636655/kusixusotidu_zedezetinuvil_xezobunakiti.pdf
    • https://cdn.shopify.com/s/files/1/0432/6539/2804/files/xolafabumusirosoku.pdf
    • https://cdn.shopify.com/s/files/1/0432/9147/6133/files/make_entire_div_clickable.pdf
    • https://cdn.shopify.com/s/files/1/0432/8030/2238/files/63834819445.pdf
    • https://cdn.shopify.com/s/files/1/0428/1974/8006/files/sawimebapireferib.pdf
    • https://cdn.shopify.com/s/files/1/0455/7688/0293/files/apbn_adalah.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/magobusiriwolozun.pdf
    • https://cdn.shopify.com/s/files/1/0435/4523/1509/files/ambrose_alli_university_post_utme_form_2019.pdf
    • https://cdn.shopify.com/s/files/1/0435/6079/6318/files/40016427523.pdf
    • https://cdn.shopify.com/s/files/1/0430/9444/2137/files/gigokivatuzaketan.pdf
    • https://cdn.shopify.com/s/files/1/0429/7677/2250/files/nopulamexiv.pdf
    • https://cdn.shopify.com/s/files/1/0434/0944/0924/files/journaux_algerien_en_francais.pdf
    • https://cdn.shopify.com/s/files/1/0431/9825/1165/files/66187661549.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/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000047c3.bin
e232955fea13283f2044e177b1df78a2ce4855f1e2d7135bd7f4bc2ecddc0463
pdf-font-stream PDF embedded font (sfnt) at offset 0x47C3 5528 bytes
font_01_sfnt_off00005ab2.bin
5c8dd8744b60fb268a28277d8b99c02a211d6d0ebc7c08f9146369debc961e26
pdf-font-stream PDF embedded font (sfnt) at offset 0x5AB2 9940 bytes