Malicious PDF — malware analysis report

Static analysis result for SHA-256 68efa6c3aed3ba05…

MALICIOUS

PDF

45.3 KB Created: 2020-08-20 11:33:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: baca4b42fdbab104c720c0577b921e0a SHA-1: 8970a3a2a2f7b8f2d919c46e6c1958b29f939eb9 SHA-256: 68efa6c3aed3ba050241be101367aff935d8298c853d4bf4e3adcfbd264ed39a
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many pointing to external PDF files, characteristic of a link farm. One of these links, https://ttraff.ru/pify?keyword=fractions+and+percentages+worksheets+year+5, is identified as a malicious redirector. The ML classifier also strongly indicated maliciousness. The sample's purpose appears to be to distribute or link to other malicious content.

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=fractions+and+percentages+worksheets+year+5
    • http://files.windsoressexcpr.com/uploads/1/3/0/9/130969740/komenijejitutivep.pdf
    • http://files.sextonslegal.com/uploads/1/3/1/4/131482878/4120390.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0434/9578/4600/files/kuletigipizutivuv.pdf
    • https://cdn.shopify.com/s/files/1/0431/5247/4267/files/70966022347.pdf
    • https://cdn.shopify.com/s/files/1/0427/3173/3159/files/durikibuviz.pdf
    • https://cdn.shopify.com/s/files/1/0432/6929/2188/files/beats_x_earphones_manual.pdf
    • https://cdn.shopify.com/s/files/1/0431/2485/0842/files/94313234445.pdf
    • https://cdn.shopify.com/s/files/1/0436/3331/1904/files/betapavorujijo.pdf
    • https://cdn.shopify.com/s/files/1/0435/4097/1674/files/5302014590.pdf
    • https://cdn.shopify.com/s/files/1/0432/2823/3883/files/food_crossword_puzzles.pdf
    • https://cdn.shopify.com/s/files/1/0433/4118/5189/files/5156344463.pdf
    • https://cdn.shopify.com/s/files/1/0428/8148/2919/files/50328623940.pdf
    • https://cdn.shopify.com/s/files/1/0436/1243/8685/files/libros_de_isabel_allende_paula.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/dojezurin.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_off00007158.bin
81834bde80c680ace21f3f5cf4e76fa2eda804703547e0c4d15dd95582b380de
pdf-font-stream PDF embedded font (sfnt) at offset 0x7158 5640 bytes
font_01_sfnt_off0000849e.bin
0c61ed596d79ad7cf07849dc738129c85dce25b029b87dcf563605b642f65b27
pdf-font-stream PDF embedded font (sfnt) at offset 0x849E 10468 bytes